WEBVTT

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PROFESSOR PATRICK WINSTON:
You know, some

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of you who for instance--

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I don't know, Sonya,
Krishna, Shoshana--

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some of you I can count on
being here every time.

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Some of you show up
once in a while.

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The ones of you who show up once
in a while happen to be

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very lucky if you picked today,
because what we're

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going to do today is I'm going
to tell you stuff that might

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make a big difference
in your whole life.

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Because I'm going to tell
you how you can

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make yourself smarter.

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No kidding.

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And I'm also going to tell you
how you can package your ideas

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so you'll be the one that's
picked instead

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of some other slug.

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So that's what we're
going to do today.

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It's the most important lecture
of the semester.

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The sleep lecture is only the
second most important.

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This is the most important.

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Now the vehicle that's going
to get us there is a

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discussion about how it's
possible to learn in a way

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that is a little reminiscent
of what we

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talked about last time.

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Because last time we learned
something very definite from a

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small number of examples.

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This takes it one step further
and shows how it's possible to

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learn in a human-like way from
a single example in one shot.

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So it's extremely different,
very different from everything

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you've seen before.

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Everything that involves
learning from thousands of

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trials and gazillions of
examples and only learning a

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little tiny bit, if anything,
from each of them.

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This is going to
learn something

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definite from every example.

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So here's the classroom
example.

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What's this?

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It's an arch.

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I know the architects are
complaining that it's not an

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arch in architecture land.

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It's a post and lintel
construction.

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But for us today it's
going to be an arch.

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Now if you were from Mars and
didn't know what an arch was,

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I might present this to you and
you'd get a general idea

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of some things that might be
factors, but you'd have no

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idea what's really important.

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So then I would say,
that's not an arch.

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And you would learn something
very definite from that.

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And then I would shove these
together and put this back on,

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and I would say, that's
not an arch either.

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And you'd learn something
very definite from that.

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And then I could paint the top
one blue, and you'd learn

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something very different
from that.

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And how can that happen
is the question?

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How can that happen in detail,
and what might it mean for

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human learning and how you can
make yourself smarter?

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And that's where we're
going to go.

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All right?

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So how can we make a program
that's a smart as a martian

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about learning things
like that?

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Well, if you were writing that
program, surely the first

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thing you would do is you'd try
to get off the picture as

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quickly as possible and into
symbol land where things are

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clearer about what the
important parts are.

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So you'd be presented with an
initial example that might

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look like this.

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We'll call that an example.

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And it's more than
just an example.

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It's the initial model.

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That's the starting point.

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And now we're going to couple
that with something that's not

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actually an arch but looks a
whole lot like one, at least

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on the descriptive level to
which we're about to go.

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So here's something that's not
an arch, but its description

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doesn't differ from that
of an arch very much.

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In fact, if we were to draw this
out in a kind of network,

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we would have a description
that looks like this, and

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these relations would be
support relations.

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And this would be drawn
out like so.

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And the only difference
would be--

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the only difference would be
that those support relations

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that we had in the
initial model--

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the example--

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have disappeared down out here
in this configuration.

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But since it's not very
different from the model,

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we're going to call
this a near miss.

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And now, you see, we've
abstracted away from all the

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details that don't
matter to us.

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Last time we talked about a
good representation having

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certain qualities--

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qualities like making the
right things explicit.

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Well, this makes the structure
explicit, and it suppresses

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information about blemishes
on the surface.

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We don't care much about how
tall the objects are.

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We don't think it matters
what they're made of.

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So this is a representation that
satisfies the first of

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the criteria from last time.

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It makes the right
things explicit.

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And by making the right things
explicit, it's exposing some

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constraint here with
respect to what it

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takes to be an arch.

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And we see that if those support
relations are missing,

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it's not an arch.

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So we ought to be able to learn
something from that.

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What we're going to do is we're
going to put these two

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things together.

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We're going to describe the
difference between the two.

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And we're going to reach the
conclusion that since there's

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only one difference--

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one kind of difference with
two manifestations to

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disappearing support relations,
we're going to

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conclude that those support
relations are important.

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And we're going to
turn them red

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because they're so important.

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And we're going to change the
name from "support" to "must

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support."

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So this is our new model.

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This is an evolving model that
now is decorated with

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information about what's
important.

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So if you're going to match
something against this model,

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it must be the case that those
support relations are there.

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If it's not there-- if they're
not there, it's not an arch.

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All right?

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So we've learned something
definite

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from a single example.

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This is not 10,000 trials.

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This is a teacher presenting
something to the student and

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the student learning something
immediately in one step about

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what's important in an arch.

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So let's do it again.

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That was so much fun.

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Let's do this one.

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Same as before except that now
when we describe this thing,

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there are some additional
relations--

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these relations, and those
are touch relations.

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So now when we compare that--

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is that an arch?

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No.

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It's a near miss.

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When we compare that near miss
with our evolving model, we

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see immediately that once again
there's exactly one

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difference, two

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manifestations, the touch relations.

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So we can immediately conclude
that these touch relations are

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interfering with our belief that
this could be an arch.

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So what do we do with that?

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We put those together
again and we build

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ourselves a new model.

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It's much like the old model.

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It still has the imperatives
up here.

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We have to have the
support relations.

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But now down here-- and we draw
not signs through there--

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these are must not
touch relations.

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So now you can't match against
that model if those two side

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supports are touching
each other.

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So in just two steps, we've
learned two important things

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about what has to be in place in
order for this thing to be

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construed to be an arch.

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So our martian is making
great progress.

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But our martian isn't through,
because there's some more

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things we might want
it to know about

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the nature of arches.

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For example, we might present
it with this one.

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Well, that looks just like
our initial example.

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It's an example just like
our initial example.

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But this time the top has
been painted red.

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And I'm still saying that
that's an arch.

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So once again, there's only
one difference and that

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difference is that in the
description of this object, we

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have the additional information
that the color of

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the top is red.

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And we've been carrying along
without saying so, that the

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color of the top in the evolving
model is white.

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So now we know that the top
doesn't have to be white.

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It can be either red or white.

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So we'll put those
two together and

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we'll get a new model.

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And that new model this
time once again

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will have three parts.

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It will have the relations, an
imperative form that we've

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been carrying along now, the
must support and the must not

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touch, but now we're going to
turn that color relation

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itself into an imperative.

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And we're going to say that
the top has to be

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either red or white.

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So now, once again, in one step
we've learned something

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definite about archness.

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Two more steps.

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Suppose now we present
it with this example.

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It's an example.

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And this time there's going
to be a little paint

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added here as well.

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This time we're going to have
the top painted blue like so.

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So the description
will be like so.

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And now we have to somehow put
that together with our

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evolving model to make
a new model.

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And there's some choices here.

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And our choice depends somewhat
on the nature of the

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world that we're working in.

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So suppose we're working
in flag world.

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There are only three colors--

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red, white, and blue.

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Now we've seen them all.

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If we've seen them all, then
what we're going to do is

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we're going to say that the
evolving model now is adjusted

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yet again like so.

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Oh-- but those are imperatives
still.

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Let me carry that along.

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At this time, this guy--

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the color relation--

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goes out here to anything
at all.

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So we could have just not drawn
it at all, but then we

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would have lost track of the
fact that we've actually

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learned that anything
can be there.

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So we're going to retain the
relation but have it point to

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the "anything goes" marker.

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Well, we're making great
progress and I said there's

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just one more thing to go.

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So let me compress that
into this area here.

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What I'm going to add this time
is I'm going to say that

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the example is like everything
you've seen before except that

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the top is now one of those
kinds of child's bricks.

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So you have a choice actually
about whether this

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is an arch or not.

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But if I say, yeah, it's still
an arch, then we'd add a

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little something to
its description.

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So this description would
look like this.

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Same things that we've seen
before in terms of support,

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but now we'd have a relation
that says that

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this top is a wedge.

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And over here--

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something we've been carrying
along but not writing down--

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this top is a block.

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A brick, I guess in the
language of the day.

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So if we say that it can be
either a wedge or a brick on

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top, what do we do with that?

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Once again, it depends on the
nature of representation, but

00:12:37.430 --> 00:12:39.980
if we say that we have a
representation, that has a

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hierarchy of parts.

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So bricks and wedges are both
children's blocks and

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children's box or toys.

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Then we can think of drawing
in a little bit of that

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hierarchy right here and
saying well, let's see.

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Immediately above that we've
got the brick or wedge.

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And a little bit above
that we've got block.

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And a little bit above
that we've got toy.

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And a little bit above that
we eventually get to

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any physical object.

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So what does it do in response
to that kind of situation?

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You have the choice.

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But what the program I'm
speaking of actually did was

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to make a conservative
generalization up here just to

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say that it's one
of those guys.

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So once again it's learned
something definite.

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Let me see.

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Let me count the steps.

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One, two, three, four, five.

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And I just learned
four things.

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So the generalization of a
color, it took two steps to

00:13:56.290 --> 00:13:59.300
get all the way up
to "don't care."

00:13:59.300 --> 00:14:02.460
So note how it contrasts with
anything you've seen in a

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neural net.

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Or anything you will see
downstream in some of the

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other learning techniques that
we'll be talking about that

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involve using thousands of
samples to learn what it is--

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to learn whatever it is that
is intended to be learned.

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Let me show you another
example of how these

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heuristics can be put to work.

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So there are two sets
of drawings.

00:14:40.510 --> 00:14:43.110
We have the upper set
and the lower set.

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And your task, you smart
humans working in vast

00:14:46.360 --> 00:14:50.100
parallelism, your task is to
give me a description of the

00:14:50.100 --> 00:14:53.740
top trains that distinguishes
and separates them from the

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trains on the bottom.

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You got it?

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Nobody's got it?

00:15:16.690 --> 00:15:18.920
Well, let me try one on you.

00:15:18.920 --> 00:15:21.830
The top trains all have a short
car with a closed top.

00:15:25.010 --> 00:15:27.235
So how is it possible that
a computer could have

00:15:27.235 --> 00:15:29.450
figured that out?

00:15:29.450 --> 00:15:31.380
It turns out that it figured
it out with much the same

00:15:31.380 --> 00:15:33.220
apparatus that I've shown you
here in connection with the

00:15:33.220 --> 00:15:37.640
arches, just deployed in a
somewhat different manner.

00:15:37.640 --> 00:15:40.680
In this particular case, the
examples are presented one at

00:15:40.680 --> 00:15:43.750
a time by a teacher
who's eager for

00:15:43.750 --> 00:15:45.610
the student to learn.

00:15:45.610 --> 00:15:49.950
In this case, the examples are
presented all at once and the

00:15:49.950 --> 00:15:52.720
machine is expected to figure
out a description that

00:15:52.720 --> 00:15:55.820
separates the two groups.

00:15:55.820 --> 00:15:57.070
And here's how it works.

00:16:01.950 --> 00:16:16.210
What you do is you start
with one of them.

00:16:16.210 --> 00:16:17.570
But you have a lot of them.

00:16:17.570 --> 00:16:18.530
You have some examples--

00:16:18.530 --> 00:16:21.700
we'll call the examples on top
the "plus examples" and the

00:16:21.700 --> 00:16:28.500
examples on the bottom the
"negative examples." So the

00:16:28.500 --> 00:16:31.020
first thing that you do is you
pick one of the positive

00:16:31.020 --> 00:16:33.810
examples to work with.

00:16:33.810 --> 00:16:35.790
Anybody got any good guesses
about what we're

00:16:35.790 --> 00:16:37.640
going to call that?

00:16:37.640 --> 00:16:38.480
Yeah, you do.

00:16:38.480 --> 00:16:39.730
We're going to call
that the seed.

00:16:42.310 --> 00:16:45.770
It's just highly reminiscent of
what we did last time when

00:16:45.770 --> 00:16:46.790
we were doing [? phonology ?]

00:16:46.790 --> 00:16:48.785
but now at a much
different level.

00:16:48.785 --> 00:16:51.350
We're going to pick one of those
guys to be the seed, and

00:16:51.350 --> 00:16:55.000
then we're going to take these
heuristics and we're going to

00:16:55.000 --> 00:16:58.690
search for one that loosens this
description so that it

00:16:58.690 --> 00:17:00.510
covers more of the positives.

00:17:00.510 --> 00:17:03.390
You see, if you have a seed that
is exactly a description

00:17:03.390 --> 00:17:07.010
of a particular thing and you
insist that everything be just

00:17:07.010 --> 00:17:10.750
like that, then nothing will
match except itself.

00:17:10.750 --> 00:17:14.098
But you can use these heuristics
to expand the

00:17:14.098 --> 00:17:17.800
coverage of the description, to
loosen it so that it covers

00:17:17.800 --> 00:17:19.540
more of the positives.

00:17:19.540 --> 00:17:24.700
So in your first step you might
cover, for example, that

00:17:24.700 --> 00:17:26.810
group of objects.

00:17:26.810 --> 00:17:30.860
Too bad for your side, you've
also in that particular case

00:17:30.860 --> 00:17:34.600
included a negative example in
your description, but perhaps

00:17:34.600 --> 00:17:38.070
in this next step beyond that
you'll get to the point where

00:17:38.070 --> 00:17:42.020
you've eliminated all of those
negative examples and zeroed

00:17:42.020 --> 00:17:46.160
in on all the positive
examples.

00:17:46.160 --> 00:17:49.810
So how might a program be
constructed that would do that

00:17:49.810 --> 00:17:50.500
sort of thing?

00:17:50.500 --> 00:17:52.140
Well, think about the choices.

00:17:52.140 --> 00:17:57.920
The first choice that you have
it is to pick a positive

00:17:57.920 --> 00:18:00.950
example to be the seed.

00:18:03.650 --> 00:18:05.880
And once you've picked a
particular example to be the

00:18:05.880 --> 00:18:09.350
seed, then you can apply
heuristics, all of them that

00:18:09.350 --> 00:18:12.820
you have, to make a new
description that may cover the

00:18:12.820 --> 00:18:13.530
data better.

00:18:13.530 --> 00:18:15.350
It may have more of the
positives and fewer of the

00:18:15.350 --> 00:18:19.150
negatives than in your
previous step.

00:18:19.150 --> 00:18:23.880
But this, if you have a lot of
heuristics, and these are a

00:18:23.880 --> 00:18:25.850
lot of heuristics because
there's a lot of description

00:18:25.850 --> 00:18:29.250
in that set of trains, there
are lots of possible things

00:18:29.250 --> 00:18:31.100
that you could do with those
heuristics because you could

00:18:31.100 --> 00:18:32.820
apply them anywhere.

00:18:32.820 --> 00:18:35.990
So this tree is extremely
large.

00:18:39.870 --> 00:18:43.080
So what do you do to keep
it under control?

00:18:43.080 --> 00:18:46.240
Well, now you have answers
to questions like that by

00:18:46.240 --> 00:18:47.480
knee-jerk, right?

00:18:47.480 --> 00:18:49.680
The branching factor
is too big.

00:18:49.680 --> 00:18:52.810
You want to keep a few
solutions going.

00:18:52.810 --> 00:18:55.700
You have some way of measuring
how well you're doing so you

00:18:55.700 --> 00:18:59.130
can use a beam search.

00:18:59.130 --> 00:19:02.880
This piece here was originally
worked out by a friend of

00:19:02.880 --> 00:19:04.930
mine, now, alas, deceased,
[? Rashad ?]

00:19:04.930 --> 00:19:05.610
[? Malkowski ?]

00:19:05.610 --> 00:19:07.000
when he was at the University
of Illinois.

00:19:07.000 --> 00:19:09.355
And of course, he wasn't
interested in toy trains, he

00:19:09.355 --> 00:19:12.150
was just interested in
soybean diseases.

00:19:12.150 --> 00:19:16.080
And so this exact program was
used to build descriptions of

00:19:16.080 --> 00:19:16.960
soybean diseases.

00:19:16.960 --> 00:19:18.170
It turned out to be
better than the

00:19:18.170 --> 00:19:19.420
plant pathology books.

00:19:23.920 --> 00:19:27.200
We now have two ways of
deploying the same heuristics.

00:19:27.200 --> 00:19:33.210
But my vocabulary is in need
of enrichment, because I'm

00:19:33.210 --> 00:19:35.880
talking about "those"
heuristics.

00:19:35.880 --> 00:19:38.010
And one of the nice things
that [? Malkowski ?]

00:19:38.010 --> 00:19:41.490
did for me a long time ago is
give each of them a name.

00:19:41.490 --> 00:19:45.160
So here are the names that
were developed by

00:19:45.160 --> 00:19:46.510
[? Malkowski. ?]

00:19:46.510 --> 00:19:47.240
What's happening here?

00:19:47.240 --> 00:19:52.430
You're going from an original
model to an understanding--

00:19:52.430 --> 00:19:54.550
some things are essential.

00:19:54.550 --> 00:19:57.140
So he called this the "require
link" heuristic.

00:20:03.590 --> 00:20:06.860
And here in the next step, we're
forbidding some things

00:20:06.860 --> 00:20:08.290
from being there.

00:20:08.290 --> 00:20:09.070
So [? Malkowski ?]

00:20:09.070 --> 00:20:11.510
called that heuristic the
"forbid link" heuristic.

00:20:17.310 --> 00:20:19.080
And in the next step, we're
saying it can be

00:20:19.080 --> 00:20:20.500
either red or white.

00:20:20.500 --> 00:20:22.850
So we have a set of colors
and we're extending it.

00:20:29.400 --> 00:20:33.010
And over here in this heuristic,
going from red or

00:20:33.010 --> 00:20:37.090
white to anything goes, that's
essentially forgetting about

00:20:37.090 --> 00:20:42.250
color altogether, so we're going
to call that "drop link"

00:20:42.250 --> 00:20:45.680
even though for reasons of
keeping track, we don't

00:20:45.680 --> 00:20:46.420
actually get rid of it.

00:20:46.420 --> 00:20:50.210
We just have it pointing to
the "anything" marker.

00:20:50.210 --> 00:20:54.950
And finally, in this last step,
what we're doing with

00:20:54.950 --> 00:21:00.090
this tree of categories is we're
climbing up it one step.

00:21:00.090 --> 00:21:01.900
So he called that the "climb
tree" heuristic.

00:21:05.070 --> 00:21:07.670
So now we have a vocabulary
of things we can do in the

00:21:07.670 --> 00:21:11.950
learning process, and having
that vocabulary gives us power

00:21:11.950 --> 00:21:12.470
over it, right?

00:21:12.470 --> 00:21:14.130
Because those are names.

00:21:14.130 --> 00:21:15.686
We can now say, well, what
you need here is

00:21:15.686 --> 00:21:17.360
the "drop link" heuristic.

00:21:17.360 --> 00:21:22.910
And what you need over there is
the "extend set" heuristic.

00:21:22.910 --> 00:21:25.860
So now I want to back up
yet another time and

00:21:25.860 --> 00:21:28.850
say, well, let's see.

00:21:28.850 --> 00:21:30.870
When we were working with that
phonology stuff, all I did was

00:21:30.870 --> 00:21:31.350
generalize.

00:21:31.350 --> 00:21:34.090
Are we just generalizing here?

00:21:34.090 --> 00:21:35.560
No.

00:21:35.560 --> 00:21:38.780
We're both generalizing
and specializing.

00:21:38.780 --> 00:21:43.520
So when I say that the links
over here that are developed

00:21:43.520 --> 00:21:48.050
in our first step are
essential, this is a

00:21:48.050 --> 00:21:49.710
specialization step.

00:21:54.760 --> 00:21:57.560
And when I say they can't be--

00:21:57.560 --> 00:21:59.880
they cannot be touch
relations, that's a

00:21:59.880 --> 00:22:01.130
specialization step.

00:22:04.880 --> 00:22:08.480
Because we're able to match
fewer and fewer things when we

00:22:08.480 --> 00:22:11.090
say you can't have
touch relations.

00:22:11.090 --> 00:22:13.940
But over here, when I go here
and say, well, it doesn't have

00:22:13.940 --> 00:22:14.640
to be white.

00:22:14.640 --> 00:22:17.220
It can also be red.

00:22:17.220 --> 00:22:18.470
That's a generalization.

00:22:21.280 --> 00:22:23.970
Now we can match more things.

00:22:23.970 --> 00:22:27.210
And when I drop the link
altogether, that's a

00:22:27.210 --> 00:22:28.460
generalization.

00:22:31.170 --> 00:22:34.005
And when I climb the tree,
that's a generalization.

00:22:40.150 --> 00:22:44.770
And that's why when I do this
notional picture of what

00:22:44.770 --> 00:22:46.030
happens when [? Malkowski ?]

00:22:46.030 --> 00:22:48.380
program does a tree search to
find a solution to the train

00:22:48.380 --> 00:22:51.680
problem, they're both
specialization steps which

00:22:51.680 --> 00:22:53.740
draw in the number of things
that can be matched, and

00:22:53.740 --> 00:22:55.485
generalization steps that
make it broader.

00:22:58.180 --> 00:23:00.670
So, let's see.

00:23:00.670 --> 00:23:05.530
We've also got the notion
of near miss.

00:23:05.530 --> 00:23:07.220
And we've got the notion
of example--

00:23:07.220 --> 00:23:08.450
some of these things
are examples,

00:23:08.450 --> 00:23:09.890
some are near misses.

00:23:09.890 --> 00:23:13.090
We've got generalization
specialization.

00:23:13.090 --> 00:23:17.290
Does one go with one or the
other, or are they all mixed

00:23:17.290 --> 00:23:19.330
up in their relationship
to each other?

00:23:19.330 --> 00:23:22.490
Can you generalize and
specialize with near misses?

00:23:22.490 --> 00:23:24.310
What do you think?

00:23:24.310 --> 00:23:25.570
You think--

00:23:25.570 --> 00:23:27.146
you don't think so,
[INAUDIBLE]?

00:23:27.146 --> 00:23:28.132
What do you think?

00:23:28.132 --> 00:23:29.611
STUDENT: [INAUDIBLE]

00:23:29.611 --> 00:23:30.104
specialization.

00:23:30.104 --> 00:23:31.090
PROFESSOR PATRICK WINSTON:
[INAUDIBLE] lead to

00:23:31.090 --> 00:23:32.569
specialization.

00:23:32.569 --> 00:23:35.050
Let's see if that's right.

00:23:35.050 --> 00:23:39.380
So we've got specialization
here, and that's a near miss.

00:23:39.380 --> 00:23:44.050
We've got specialization here,
and that's a near miss.

00:23:44.050 --> 00:23:49.430
We've got generalization here,
and that's an example.

00:23:49.430 --> 00:23:53.540
And we've got generalization
here, and that's an example.

00:23:53.540 --> 00:23:56.550
And we've got generalization
here, and that's an example.

00:23:56.550 --> 00:23:59.000
So [INAUDIBLE] has got
that one nailed.

00:23:59.000 --> 00:24:01.650
The examples always generalize,
and the near

00:24:01.650 --> 00:24:02.910
misses always specialize.

00:24:02.910 --> 00:24:05.580
So we've got apparatuses in
place that allow us to both

00:24:05.580 --> 00:24:10.910
expand what we could match and
shrink what we could match.

00:24:10.910 --> 00:24:12.380
So what has this got
to do anything?

00:24:12.380 --> 00:24:16.260
Well, which one of these methods
is better, by the way?

00:24:16.260 --> 00:24:17.920
This one--

00:24:17.920 --> 00:24:20.780
this one requires a teacher
to organize everything up.

00:24:20.780 --> 00:24:26.320
This one can handle
it in batch mode.

00:24:26.320 --> 00:24:29.600
This one is the sort of thing
you would need to do with a

00:24:29.600 --> 00:24:31.900
human because we don't
have much memory.

00:24:31.900 --> 00:24:33.970
That one is the sort of thing
that a computer's good at

00:24:33.970 --> 00:24:35.790
because it has lots of memory.

00:24:35.790 --> 00:24:38.690
So which one's better?

00:24:38.690 --> 00:24:41.010
Well, it depends on what
you're trying to do.

00:24:41.010 --> 00:24:44.425
If you're trying to build a
machine that analyzes the

00:24:44.425 --> 00:24:46.610
stock market, you might
want to go that way.

00:24:46.610 --> 00:24:50.540
Or soybean diseases, or
any one of a variety

00:24:50.540 --> 00:24:51.290
of practical problems.

00:24:51.290 --> 00:24:54.440
If you're trying to model
people, then maybe this is a

00:24:54.440 --> 00:24:57.690
way that deserves additional
merit.

00:24:57.690 --> 00:24:59.450
How do you get all
that sorted out?

00:24:59.450 --> 00:25:03.840
Well, one way to get it all
sorted out is to talk in terms

00:25:03.840 --> 00:25:12.875
of what are sometimes called
"felicity conditions." So when

00:25:12.875 --> 00:25:14.570
I talk about felicity
conditions, I'm talking about

00:25:14.570 --> 00:25:16.980
a teacher and a student
and covenants that

00:25:16.980 --> 00:25:18.710
hold between them.

00:25:18.710 --> 00:25:20.655
So here's the teacher.

00:25:26.100 --> 00:25:29.090
That's me.

00:25:29.090 --> 00:25:30.340
And here's the student.

00:25:33.980 --> 00:25:35.230
That's you.

00:25:37.270 --> 00:25:44.200
And the objective of interaction
is to transform an

00:25:44.200 --> 00:25:57.560
initial state of knowledge into
a new state of knowledge

00:25:57.560 --> 00:26:04.465
so that the student is smarter
and able to make use of that

00:26:04.465 --> 00:26:11.565
new knowledge to do things that
couldn't be done before

00:26:11.565 --> 00:26:13.950
by the student.

00:26:13.950 --> 00:26:15.655
So the student over here
has a learner.

00:26:22.150 --> 00:26:26.005
And he has something that
uses what is learned.

00:26:29.310 --> 00:26:31.620
And the teacher over
here has a style.

00:26:34.890 --> 00:26:39.720
So if any learning is to take
place, one side has to know

00:26:39.720 --> 00:26:42.230
something about the
other side.

00:26:42.230 --> 00:26:52.440
For example, it's helpful if
the teacher understands the

00:26:52.440 --> 00:26:55.200
initial state of the student.

00:26:55.200 --> 00:26:58.050
And here's one way of
thinking about that.

00:27:16.830 --> 00:27:20.350
You can think of what you know
as forming a kind of network.

00:27:20.350 --> 00:27:23.750
So initially, you don't
know anything.

00:27:23.750 --> 00:27:26.780
But as you learn, you start

00:27:26.780 --> 00:27:28.295
developing quanta of knowledge.

00:27:37.620 --> 00:27:40.360
And these quanta of knowledge
are all linked together by

00:27:40.360 --> 00:27:44.410
prerequisite relationships that
might indicate how you

00:27:44.410 --> 00:27:47.130
get from one quantum
to another.

00:27:47.130 --> 00:27:49.200
So maybe you have generalization
links, maybe

00:27:49.200 --> 00:27:51.560
you have specialization links,
maybe you have combination

00:27:51.560 --> 00:27:54.420
links, but you can think of what
you know as forming this

00:27:54.420 --> 00:27:56.590
kind of network.

00:27:56.590 --> 00:27:59.640
Now your state of knowledge at
any particular time can then

00:27:59.640 --> 00:28:04.700
be viewed as a kind of wavefront
in that space.

00:28:04.700 --> 00:28:08.020
So if I, the teacher, know where
your wavefront is, can I

00:28:08.020 --> 00:28:10.990
do a better job of teaching
you stuff?

00:28:10.990 --> 00:28:13.510
Sure, for this reason.

00:28:13.510 --> 00:28:20.130
Suppose you make a mistake,
m1, that depends on q1.

00:28:20.130 --> 00:28:22.600
Way, way behind your
wavefront.

00:28:22.600 --> 00:28:24.230
What do I do if I know
that you made a

00:28:24.230 --> 00:28:26.935
mistake of that kind?

00:28:26.935 --> 00:28:30.620
Oh, I just say, oh, you forgot
you need a semicolon after

00:28:30.620 --> 00:28:32.450
that kind of statement.

00:28:32.450 --> 00:28:34.710
I just remind you of something
that you certainly know, you

00:28:34.710 --> 00:28:36.560
just overlooked.

00:28:36.560 --> 00:28:37.720
Right?

00:28:37.720 --> 00:28:42.030
On the other hand, suppose you
make a mistake that depends on

00:28:42.030 --> 00:28:44.620
a piece of knowledge
way out here.

00:28:44.620 --> 00:28:46.590
That kind of mistake, m2.

00:28:46.590 --> 00:28:50.075
What do I say to you then?

00:28:50.075 --> 00:28:52.480
What do you think, Patrick?

00:28:52.480 --> 00:28:53.245
What do you think I would
say if you made

00:28:53.245 --> 00:28:55.021
that kind of mistake?

00:28:55.021 --> 00:28:56.969
STUDENT: [INAUDIBLE].

00:28:56.969 --> 00:28:57.943
PROFESSOR PATRICK WINSTON: No.

00:28:57.943 --> 00:29:02.813
That's not what I would
say [INAUDIBLE].

00:29:02.813 --> 00:29:05.248
STUDENT: You'd tell us that
we don't know that yet.

00:29:05.248 --> 00:29:07.196
PROFESSOR PATRICK WINSTON: I
would say something like that.

00:29:07.196 --> 00:29:10.140
What [INAUDIBLE] suggested
I would say.

00:29:10.140 --> 00:29:12.470
Oh, don't worry about that.

00:29:12.470 --> 00:29:13.420
We'll get to it.

00:29:13.420 --> 00:29:15.770
We're not ready for it yet.

00:29:15.770 --> 00:29:19.030
So in this case, I remind
somebody of something they

00:29:19.030 --> 00:29:20.360
already know.

00:29:20.360 --> 00:29:23.370
In this case, I tell them
they'll learn about it later.

00:29:23.370 --> 00:29:27.550
So what do I do with mistake
number three?

00:29:27.550 --> 00:29:29.710
That's the learning moment.

00:29:29.710 --> 00:29:31.960
That's where I can push
the wavefront out.

00:29:31.960 --> 00:29:33.550
Because everything's in
place to learn the

00:29:33.550 --> 00:29:36.770
stuff at the next radius.

00:29:36.770 --> 00:29:38.770
So if I know that the student
has made a mistake on that

00:29:38.770 --> 00:29:41.490
wavefront, that's when I say,
this is the teaching moment.

00:29:41.490 --> 00:29:43.500
This is when I explain
something.

00:29:43.500 --> 00:29:48.290
So that's why it's important for
the teacher to have a good

00:29:48.290 --> 00:29:52.860
model of where the
student is in the

00:29:52.860 --> 00:29:54.110
initial state of knowledge.

00:29:56.910 --> 00:30:00.970
Next thing that's important for
the teacher to know is the

00:30:00.970 --> 00:30:03.220
way that the student learns.

00:30:03.220 --> 00:30:05.290
Because if the student is a
computer, they can handle the

00:30:05.290 --> 00:30:06.030
stuff in batch.

00:30:06.030 --> 00:30:07.280
That's one thing.

00:30:07.280 --> 00:30:10.810
If the student is a third
grader who has a limited

00:30:10.810 --> 00:30:14.880
capacity to store stuff, then
that makes a difference in how

00:30:14.880 --> 00:30:15.370
you teach it.

00:30:15.370 --> 00:30:19.260
You might teach it that way to
the third grader, and that

00:30:19.260 --> 00:30:23.080
way, buried underneath this
board, to a computer.

00:30:23.080 --> 00:30:25.810
So you need to understand the
way that the learner--

00:30:25.810 --> 00:30:30.130
the computational capacity
of the learner.

00:30:30.130 --> 00:30:32.610
And there's also a need to
understand the computational

00:30:32.610 --> 00:30:38.160
capacity of the user box down
there, because sometimes you

00:30:38.160 --> 00:30:42.120
can be taught stuff that
you can't actually use.

00:30:42.120 --> 00:30:44.550
So by now, most of you have
attempted to read that

00:30:44.550 --> 00:30:46.920
sentence up there, right?

00:30:46.920 --> 00:30:49.690
And it seems screwy, right?

00:30:49.690 --> 00:30:52.970
It seems unintelligible,
perhaps?

00:30:52.970 --> 00:30:54.350
It's a garden path sentence.

00:30:54.350 --> 00:30:57.750
It makes perfectly good English,
but the way you

00:30:57.750 --> 00:31:00.300
generally read it, it doesn't,
because you have a limited

00:31:00.300 --> 00:31:04.580
buffer in your language
processor.

00:31:04.580 --> 00:31:06.000
What does this mean?

00:31:06.000 --> 00:31:10.130
You're expecting this to
be "to." Question.

00:31:10.130 --> 00:31:11.680
But it's actually a command.

00:31:11.680 --> 00:31:12.820
Here's the deal.

00:31:12.820 --> 00:31:15.560
Somebody's got to give the
students their grades.

00:31:15.560 --> 00:31:18.700
Well, we can have their
parents do it.

00:31:18.700 --> 00:31:21.650
Have the grades given
to their students by

00:31:21.650 --> 00:31:23.340
their parents, then.

00:31:23.340 --> 00:31:24.180
So it's a command.

00:31:24.180 --> 00:31:25.970
And you garden path on it,
because you have limited

00:31:25.970 --> 00:31:28.230
buffer space in your
language processor.

00:31:28.230 --> 00:31:31.310
So with parentheses you
can understand it.

00:31:31.310 --> 00:31:32.520
You can learn about it.

00:31:32.520 --> 00:31:34.150
You can see that it's good
English, but you can't

00:31:34.150 --> 00:31:38.100
generally process that kind of
sentence without going back

00:31:38.100 --> 00:31:40.450
and starting over.

00:31:40.450 --> 00:31:42.140
And what about going
the other way?

00:31:42.140 --> 00:31:45.670
Are there covenants that we have
to have here that involve

00:31:45.670 --> 00:31:48.900
the student understanding some
things about the teacher?

00:31:48.900 --> 00:31:52.210
Well, first thing there
is is trust.

00:31:52.210 --> 00:31:54.690
The student has to presume that
the teacher is teaching

00:31:54.690 --> 00:31:57.420
the student correct
information,

00:31:57.420 --> 00:32:00.460
not lying to student.

00:32:00.460 --> 00:32:02.700
Ratified that you're all here
because presumably you all

00:32:02.700 --> 00:32:05.700
think that I'm not trying to
screw you by telling you stuff

00:32:05.700 --> 00:32:07.540
that's a lie.

00:32:07.540 --> 00:32:10.990
There's also this sort
of thing down here.

00:32:10.990 --> 00:32:13.440
Understanding of the
teacher's style.

00:32:13.440 --> 00:32:15.590
So you might say, well,
professor x, all he does is

00:32:15.590 --> 00:32:18.230
read slides to us in
class, so why go?

00:32:18.230 --> 00:32:19.760
You wouldn't be entirely
misadvised.

00:32:19.760 --> 00:32:22.530
That's an understanding
of one kind of style.

00:32:22.530 --> 00:32:24.620
Or you can say, well, old
Winston, he tries to tell us

00:32:24.620 --> 00:32:29.040
something definite and convey a
family of powerful ideas in

00:32:29.040 --> 00:32:29.830
every class.

00:32:29.830 --> 00:32:31.590
So maybe it's worth dragging
yourself out of bed at 10

00:32:31.590 --> 00:32:32.850
o'clock in the morning.

00:32:32.850 --> 00:32:35.850
Those are style issues, and
those are things that the

00:32:35.850 --> 00:32:39.500
student uses to determine how
to match the student's style

00:32:39.500 --> 00:32:43.370
against that of the
instructor.

00:32:43.370 --> 00:32:48.330
So that helps us to interpret or
think about differences in

00:32:48.330 --> 00:32:51.010
style so that we can appreciate
whether we ought to

00:32:51.010 --> 00:32:56.800
be learning that way, where
that way is the way that's

00:32:56.800 --> 00:32:59.520
underneath down here, the way
you would teach a computer,

00:32:59.520 --> 00:33:00.970
the way [? Malkowski ?]

00:33:00.970 --> 00:33:03.600
taught a computer about
soybean diseases.

00:33:03.600 --> 00:33:08.090
We can do it that way, or we
can do it this way with a

00:33:08.090 --> 00:33:10.570
teacher who deliberately
organizes and shapes the

00:33:10.570 --> 00:33:14.150
learning sequence for the
benefit of a student who has a

00:33:14.150 --> 00:33:18.260
limited processing capability.

00:33:18.260 --> 00:33:19.680
Now you're humans, right?

00:33:19.680 --> 00:33:22.910
So think about what the machine
has to do here.

00:33:22.910 --> 00:33:23.570
The machine--

00:33:23.570 --> 00:33:26.380
in order to learn anything
definite in each of those

00:33:26.380 --> 00:33:29.490
steps, the machine has to
build a description.

00:33:29.490 --> 00:33:32.410
So it has to describe the
examples to itself.

00:33:32.410 --> 00:33:33.450
That's unquestioned, right?

00:33:33.450 --> 00:33:36.460
Because what it's doing is
looking at the differences.

00:33:36.460 --> 00:33:38.420
So it can't look at the
differences unless it's got

00:33:38.420 --> 00:33:39.670
descriptions of things.

00:33:42.480 --> 00:33:46.630
So if you're like the machine,
then you can't learn anything

00:33:46.630 --> 00:33:49.200
unless you build descriptions.

00:33:49.200 --> 00:33:53.140
Unless you talk to yourself.

00:33:53.140 --> 00:33:56.030
And if you talk to yourself,
you're building the kind of

00:33:56.030 --> 00:33:58.340
descriptions that make
it possible for

00:33:58.340 --> 00:34:00.850
you to do the learning.

00:34:00.850 --> 00:34:04.220
And you say to me, I'm
an MIT student.

00:34:04.220 --> 00:34:06.640
I want to see the numbers.

00:34:06.640 --> 00:34:08.040
So let me show you
the numbers.

00:34:08.040 --> 00:34:10.290
And when I'm going
to show numbers--

00:34:10.290 --> 00:34:12.400
the numbers that I'm going to
show you show you the virtues

00:34:12.400 --> 00:34:15.600
of talking to yourself.

00:34:15.600 --> 00:34:18.190
So here's the experiment.

00:34:18.190 --> 00:34:21.750
The experiment was done by a
friend of mine, Michelene Chi.

00:34:21.750 --> 00:34:25.170
Always seems to go by
the name Mickey Chi.

00:34:38.130 --> 00:34:39.460
There he is.

00:34:39.460 --> 00:34:40.340
So here's the deal.

00:34:40.340 --> 00:34:44.580
The students that she worked
with were expected to learn

00:34:44.580 --> 00:34:45.989
about elementary physics.

00:34:45.989 --> 00:34:48.060
801 type stuff.

00:34:48.060 --> 00:34:52.719
And she took eight subjects,
and she had them--

00:34:52.719 --> 00:34:54.820
she took them through a bunch of
examples and then she gave

00:34:54.820 --> 00:34:57.220
them an examination.

00:34:57.220 --> 00:35:01.400
So eight subjects, and so they
divide into two groups.

00:35:01.400 --> 00:35:03.890
The bottom half and
the top half.

00:35:03.890 --> 00:35:06.750
The ones who did better than
average and the ones who did

00:35:06.750 --> 00:35:09.320
worse than average.

00:35:09.320 --> 00:35:12.740
So then you can say, well,
OK, what did that mean?

00:35:12.740 --> 00:35:14.940
You can say, how much did
they talk to themselves?

00:35:14.940 --> 00:35:17.680
Well, that was measured by
having them talk out loud as

00:35:17.680 --> 00:35:20.800
they solved the problems
on an examination.

00:35:20.800 --> 00:35:25.440
So we could ask how much self
explanation was done by the

00:35:25.440 --> 00:35:28.470
smart ones versus the
less smart ones?

00:35:28.470 --> 00:35:30.830
And here are the results.

00:35:30.830 --> 00:35:34.620
The worst ones-- the worst four
said about 10 things to

00:35:34.620 --> 00:35:36.390
themselves.

00:35:36.390 --> 00:35:42.530
The best four said about 35
things to themselves.

00:35:42.530 --> 00:35:44.470
That's a pretty dramatic
difference.

00:35:44.470 --> 00:35:48.290
Here's the data in a more
straightforward form.

00:35:48.290 --> 00:35:50.840
This, by the way, points out
that the smart ones scored

00:35:50.840 --> 00:35:54.870
twice as high as the
less smart ones.

00:35:54.870 --> 00:35:56.870
And when we look at the number
of explanations they gave

00:35:56.870 --> 00:36:01.760
themselves in two categories,
smart ones said three times as

00:36:01.760 --> 00:36:04.460
much stuff to themselves
as the less smart ones.

00:36:04.460 --> 00:36:07.760
So, as you can see, the
explanations break down into

00:36:07.760 --> 00:36:09.170
two groups.

00:36:09.170 --> 00:36:13.770
Some have to do with monitoring
and not with

00:36:13.770 --> 00:36:14.760
physics at all.

00:36:14.760 --> 00:36:18.010
They're things like,
oh hell, I'm stuck.

00:36:18.010 --> 00:36:22.250
Or, I don't know what to do.

00:36:22.250 --> 00:36:24.490
And the others have to
do with physics.

00:36:24.490 --> 00:36:27.550
Things like, well, maybe I
should draw a force diagram.

00:36:27.550 --> 00:36:32.340
Or let me write down f equals
ma, or something like that, as

00:36:32.340 --> 00:36:34.200
physics knowledge.

00:36:34.200 --> 00:36:37.975
I think it's interesting that
this average score is

00:36:37.975 --> 00:36:41.080
different by a factor of two,
and the average talking to

00:36:41.080 --> 00:36:44.580
oneself differed by
a factor of three.

00:36:44.580 --> 00:36:49.280
Now this isn't quite there,
because what's not clear is if

00:36:49.280 --> 00:36:51.900
you encourage somebody to talk
to themself, and they talk to

00:36:51.900 --> 00:36:54.570
themselves more than they would
have ordinarily, does

00:36:54.570 --> 00:36:55.770
that make them score better?

00:36:55.770 --> 00:36:58.280
All we know is that the ones who
talk to themselves more do

00:36:58.280 --> 00:36:59.890
score better.

00:36:59.890 --> 00:37:04.510
But anecdotally, talking to
some veterans of 6.034,

00:37:04.510 --> 00:37:06.240
they've started talking to
themselves more when they

00:37:06.240 --> 00:37:09.065
solve problems, and they think
that it makes them smarter.

00:37:11.830 --> 00:37:16.490
Now I would caution you not to
do this too much in public.

00:37:16.490 --> 00:37:18.590
Because people can get the
wrong idea if you talk to

00:37:18.590 --> 00:37:19.430
yourself too much.

00:37:19.430 --> 00:37:22.350
But it does seem--

00:37:22.350 --> 00:37:29.270
it does, in fact,
seem to help.

00:37:29.270 --> 00:37:32.260
Now what I did last time
is I told you how

00:37:32.260 --> 00:37:33.750
to be a good scientist.

00:37:33.750 --> 00:37:35.890
What I'm telling you now is how
to make yourself smarter.

00:37:35.890 --> 00:37:38.160
And I want to conclude this hour
by telling you about how

00:37:38.160 --> 00:37:42.670
you can package your ideas so
that they have greater impact.

00:37:42.670 --> 00:37:45.720
So I guess I could have said,
how to make yourself more

00:37:45.720 --> 00:37:49.430
famous, but I've limited
myself to saying how to

00:37:49.430 --> 00:37:50.570
package your ideas better.

00:37:50.570 --> 00:37:53.010
And the reason you want to
package your ideas better is

00:37:53.010 --> 00:37:55.260
because if you package your
ideas better than the next

00:37:55.260 --> 00:37:57.630
slug, then you're going to get
the faculty position and

00:37:57.630 --> 00:37:59.130
they're not.

00:37:59.130 --> 00:38:00.050
If you say to me, I'm
going to be an

00:38:00.050 --> 00:38:02.310
entrepreneur, same thing.

00:38:02.310 --> 00:38:03.950
You're going to get the venture
capitalist money and

00:38:03.950 --> 00:38:07.580
the next slug won't if you
package your ideas better.

00:38:07.580 --> 00:38:10.920
So this little piece of work
on the arch business got a

00:38:10.920 --> 00:38:13.600
whole lot more famous than
I ever expected.

00:38:13.600 --> 00:38:16.310
I did it when I was young and
stupid, and didn't have any

00:38:16.310 --> 00:38:19.400
idea what qualities might emerge
from a piece of work

00:38:19.400 --> 00:38:21.240
that would make it well known.

00:38:21.240 --> 00:38:23.160
I only figured it
out much later.

00:38:23.160 --> 00:38:29.310
But in retrospect, it has five
qualities that you can think

00:38:29.310 --> 00:38:31.950
about when you're deciding
whether your packaging of your

00:38:31.950 --> 00:38:37.240
idea is in a form that will
lead to that idea becoming

00:38:37.240 --> 00:38:39.490
well known.

00:38:39.490 --> 00:38:43.340
And since there are five of
them, it's convenient to put

00:38:43.340 --> 00:38:51.520
them all on the points
of a star like so.

00:38:51.520 --> 00:38:55.790
So quality number one.

00:38:55.790 --> 00:38:57.870
I've made these all into s-words
just to make them

00:38:57.870 --> 00:38:59.720
easier to remember.

00:38:59.720 --> 00:39:03.390
Quality number one is that
there's some kind of symbol

00:39:03.390 --> 00:39:05.270
associated with a work.

00:39:05.270 --> 00:39:09.560
Some kind of visual handle
that people will use to

00:39:09.560 --> 00:39:11.760
remember your idea.

00:39:11.760 --> 00:39:14.890
So what's the visual
symbol here?

00:39:14.890 --> 00:39:17.200
Well, that's astonishingly easy
to figure out, right?

00:39:17.200 --> 00:39:19.140
That's the arch.

00:39:19.140 --> 00:39:21.110
For years without my
intending it, this

00:39:21.110 --> 00:39:24.670
was called arch learning.

00:39:24.670 --> 00:39:26.840
So you need a symbol.

00:39:26.840 --> 00:39:29.760
Then you also need a slogan.

00:39:35.940 --> 00:39:37.820
That's a kind of
verbal handle.

00:39:37.820 --> 00:39:41.180
It doesn't explain the idea,
but it's enough of a handle

00:39:41.180 --> 00:39:45.280
to, as Minsky would say, put you
back in the mental state

00:39:45.280 --> 00:39:46.920
you were in when you understood
the idea in the

00:39:46.920 --> 00:39:48.540
first place.

00:39:48.540 --> 00:39:51.430
So what is the slogan
for this work?

00:39:51.430 --> 00:39:53.760
Anybody have any ideas?

00:39:53.760 --> 00:39:56.745
Pretty obvious.

00:39:56.745 --> 00:39:59.727
What's essential to this
process working?

00:39:59.727 --> 00:40:02.212
The ability to present an
example is very similar

00:40:02.212 --> 00:40:05.616
[INAUDIBLE], that constitutes
a model but

00:40:05.616 --> 00:40:06.820
isn't one of those.

00:40:06.820 --> 00:40:07.310
STUDENT: [INAUDIBLE].

00:40:07.310 --> 00:40:08.780
PROFESSOR PATRICK WINSTON:
So it's a near miss.

00:40:17.620 --> 00:40:19.700
The next thing you need if your
work is going to become

00:40:19.700 --> 00:40:21.300
well known is a surprise.

00:40:29.550 --> 00:40:32.180
What's the surprise
with this stuff?

00:40:32.180 --> 00:40:33.050
Well, the surprise--

00:40:33.050 --> 00:40:35.310
everything that had been done
in artificial intelligence

00:40:35.310 --> 00:40:37.800
having to do with learning
before this time was

00:40:37.800 --> 00:40:40.120
precursors to neural nets.

00:40:40.120 --> 00:40:42.490
Thousands of examples
to learn anything.

00:40:42.490 --> 00:40:46.410
So the big surprise was that it
was possible for a machine

00:40:46.410 --> 00:40:49.950
to learn something definite
from each of the examples.

00:40:49.950 --> 00:40:53.810
So that now goes by the name
of one shot learning.

00:40:53.810 --> 00:40:55.890
That was the surprise, that a
computer could learn something

00:40:55.890 --> 00:40:59.680
definite from a single
example.

00:40:59.680 --> 00:41:00.120
So let's see.

00:41:00.120 --> 00:41:03.630
We've almost completed
our star.

00:41:03.630 --> 00:41:05.120
But there are more
points on it.

00:41:05.120 --> 00:41:06.370
So this point is the salient.

00:41:10.530 --> 00:41:12.680
What's a salient--

00:41:12.680 --> 00:41:13.930
what's a salient idea?

00:41:16.400 --> 00:41:17.996
Jose, do you know what
a salient idea is?

00:41:20.912 --> 00:41:24.800
He's too shy to tell me.

00:41:24.800 --> 00:41:27.716
What's a salient idea?

00:41:27.716 --> 00:41:30.065
Ah, who said important?

00:41:30.065 --> 00:41:31.550
Wrong answer, but very good.

00:41:31.550 --> 00:41:34.025
You're not shy.

00:41:34.025 --> 00:41:35.510
So what does it really mean?

00:41:35.510 --> 00:41:36.500
Yes.

00:41:36.500 --> 00:41:37.490
STUDENT: Relative to
what somebody's

00:41:37.490 --> 00:41:39.470
already thinking about?

00:41:39.470 --> 00:41:40.955
PROFESSOR PATRICK WINSTON:
Relative to what somebody's

00:41:40.955 --> 00:41:41.450
thinking about.

00:41:41.450 --> 00:41:42.700
Not quite.

00:41:48.380 --> 00:41:50.360
If you have a--

00:41:50.360 --> 00:41:51.610
if you're an expert in--

00:41:53.825 --> 00:41:54.815
yes?

00:41:54.815 --> 00:41:56.300
STUDENT: [INAUDIBLE].

00:41:56.300 --> 00:41:56.795
PROFESSOR PATRICK WINSTON:
Really close.

00:41:56.795 --> 00:42:00.260
We're getting closer.

00:42:00.260 --> 00:42:01.250
[INAUDIBLE].

00:42:01.250 --> 00:42:01.745
Yes?

00:42:01.745 --> 00:42:04.467
STUDENT: Maybe an idea that
wasn't obviously apparent, but

00:42:04.467 --> 00:42:08.740
becomes apparent gradually as
somebody starts to understand?

00:42:08.740 --> 00:42:09.660
PROFESSOR PATRICK WINSTON: We're
zeroing-- we're circling

00:42:09.660 --> 00:42:12.040
the wagons here and
zeroing in on it.

00:42:12.040 --> 00:42:12.978
Yes?

00:42:12.978 --> 00:42:15.730
STUDENT: If I'm preempting what
you're about to say, it

00:42:15.730 --> 00:42:19.455
has sort of a doorway of how you
can understand the idea.

00:42:19.455 --> 00:42:19.954
PROFESSOR PATRICK WINSTON:
It's what?

00:42:19.954 --> 00:42:20.453
Sorry.

00:42:20.453 --> 00:42:22.948
STUDENT: It's sort of like
a doorway of how you

00:42:22.948 --> 00:42:26.940
can grasp the idea.

00:42:26.940 --> 00:42:29.250
PROFESSOR PATRICK WINSTON:
That's sort if it, too, but if

00:42:29.250 --> 00:42:31.700
you study military history,
what's the salient on a fort?

00:42:36.020 --> 00:42:38.090
Well, this is a good word to
have in your vocabulary

00:42:38.090 --> 00:42:41.850
because it sort of means all of
those things, but what it

00:42:41.850 --> 00:42:44.850
really means is something
that sticks out.

00:42:44.850 --> 00:42:48.660
So on a fort, if this were a
fort, these would all be

00:42:48.660 --> 00:42:51.380
salients because
they stick out.

00:42:51.380 --> 00:42:54.020
So the salient idea is
usually important

00:42:54.020 --> 00:42:55.870
because it sticks out.

00:42:55.870 --> 00:42:57.780
But it's not-- the meaning is
not "important," the meaning

00:42:57.780 --> 00:42:59.300
is "stick out."

00:42:59.300 --> 00:43:02.180
So a piece of work becomes
more famous if it has

00:43:02.180 --> 00:43:04.130
something that sticks out.

00:43:04.130 --> 00:43:04.930
It's interesting.

00:43:04.930 --> 00:43:06.840
There are theses that have been
written at MIT that have

00:43:06.840 --> 00:43:08.090
too many good ideas.

00:43:10.190 --> 00:43:12.160
And how can have too
many good ideas?

00:43:12.160 --> 00:43:15.170
Well, you can have too many
good ideas if no one idea

00:43:15.170 --> 00:43:18.120
rises above and becomes the idea
that people think about

00:43:18.120 --> 00:43:20.310
when they think about you.

00:43:20.310 --> 00:43:22.130
We have people on the faculty
who would have been more

00:43:22.130 --> 00:43:24.280
famous if their theses
had fewer ideas.

00:43:24.280 --> 00:43:26.530
It's amazing.

00:43:26.530 --> 00:43:29.670
So this piece of work
did have a salient.

00:43:29.670 --> 00:43:33.390
And the salient idea was that
you could get one shot

00:43:33.390 --> 00:43:38.920
learning via the use
of near misses.

00:43:38.920 --> 00:43:41.290
That was the salient idea.

00:43:41.290 --> 00:43:44.660
The fifth thing, ah.

00:43:44.660 --> 00:43:47.600
Talk more about this
in my "How to

00:43:47.600 --> 00:43:48.960
Speak" lecture in January.

00:43:48.960 --> 00:43:51.950
The fifth thing I like people
to try to incorporate into

00:43:51.950 --> 00:43:54.020
their presentations
is a story.

00:43:57.000 --> 00:44:00.290
Because we humans somehow
love stories.

00:44:00.290 --> 00:44:01.610
We love people to
tell us stories.

00:44:01.610 --> 00:44:03.260
We love things to be packaged
in stories.

00:44:03.260 --> 00:44:06.920
And believe me, I think all of
education is essentially about

00:44:06.920 --> 00:44:09.850
storytelling and story
understanding.

00:44:09.850 --> 00:44:12.480
So if you want your idea to
be sold to the venture

00:44:12.480 --> 00:44:16.850
capitalist, if you want to get
the faculty job, if you want

00:44:16.850 --> 00:44:19.940
to get your book sold to a
publisher, if you want to sell

00:44:19.940 --> 00:44:23.720
something to a customer, ask
yourself if your presentation

00:44:23.720 --> 00:44:25.300
has these qualities in it.

00:44:25.300 --> 00:44:28.230
And if it has all of those
things, it's a lot more likely

00:44:28.230 --> 00:44:30.120
to be effective than
it doesn't.

00:44:30.120 --> 00:44:31.550
And you'll end up
being famous.

00:44:31.550 --> 00:44:35.030
Now you say to me, well, being
famous-- that sounds like the

00:44:35.030 --> 00:44:38.020
Sloan School type of concept.

00:44:38.020 --> 00:44:39.990
Isn't it immoral to
want to be famous?

00:44:42.570 --> 00:44:45.270
Maybe that's a decision
you can make.

00:44:45.270 --> 00:44:50.880
But whenever I think about the
question, I somehow think of

00:44:50.880 --> 00:44:52.730
the idea that your ideas
are like your children.

00:44:52.730 --> 00:44:56.050
You want to be sure that they
have the best life possible.

00:44:56.050 --> 00:44:59.390
So if they're not packaged
well, they won't.

00:44:59.390 --> 00:45:06.670
I'm also reminded of an evening
I spent at a soiree

00:45:06.670 --> 00:45:10.400
with Julia Child.

00:45:10.400 --> 00:45:14.600
Julia, and there's me.

00:45:14.600 --> 00:45:16.770
And I have no idea how
come I got to sit

00:45:16.770 --> 00:45:17.700
next to Julia Child.

00:45:17.700 --> 00:45:20.600
I think they thought I was
one of the rich Winstons.

00:45:20.600 --> 00:45:23.250
The Winston flowers, or the
Harry Winston diamonds or

00:45:23.250 --> 00:45:23.960
something like that.

00:45:23.960 --> 00:45:26.700
There I was, sitting next
to Julia Child.

00:45:26.700 --> 00:45:27.940
And the interesting thing--

00:45:27.940 --> 00:45:31.379
by the way, did you notice
I'm now telling a story?

00:45:31.379 --> 00:45:36.120
The interesting thing about this
experience was that there

00:45:36.120 --> 00:45:42.760
was a constant flow
of people--

00:45:42.760 --> 00:45:44.410
happened to be all women--

00:45:44.410 --> 00:45:49.430
people going past Ms. Child
saying how wonderful she was

00:45:49.430 --> 00:45:52.840
to have made such an enormous
change in their life.

00:45:52.840 --> 00:45:53.340
Must have been 10 of them.

00:45:53.340 --> 00:45:54.190
It was amazing.

00:45:54.190 --> 00:45:56.250
Just steady flow.

00:45:56.250 --> 00:46:00.730
So eventually I leaned over to
her and I said, Ms. Child, is

00:46:00.730 --> 00:46:03.130
it fun to be famous?

00:46:03.130 --> 00:46:05.930
And she thought about it
a second and said,

00:46:05.930 --> 00:46:08.360
you get used to it.

00:46:08.360 --> 00:46:11.380
And that had a profound effect
on me, because you always say,

00:46:11.380 --> 00:46:13.810
well, what's the
opposite like?

00:46:13.810 --> 00:46:15.330
Is it fun to be ignored?

00:46:15.330 --> 00:46:20.950
And the answer is, no, it's not
much fun to be ignored.

00:46:20.950 --> 00:46:23.990
So yeah, it's something you can
get used to, but you can

00:46:23.990 --> 00:46:27.180
never get used to having your
stuff ignored, especially if

00:46:27.180 --> 00:46:28.610
it's good stuff.

00:46:28.610 --> 00:46:30.270
So that's why I commend
to you this business

00:46:30.270 --> 00:46:32.160
about packaging ideas.

00:46:32.160 --> 00:46:34.770
And now you see that 6034
is not just about AI.

00:46:34.770 --> 00:46:36.140
It's about how to
do good science.

00:46:36.140 --> 00:46:38.220
It's how to make yourself
smarter, and how to make

00:46:38.220 --> 00:46:39.470
yourself more famous.