PROFESSOR: So how are the trade-offs going to work?
What if you have to choose between a shorter,
more intense pain and a longer, less intense pain?
In order to think about this, it might
be helpful to perform a series of what philosophers
call thought experiments.
I should say something just before we
get going about what a thought experiment is.
A thought experiment in philosophy
is typically a case where we imagine a particular story
or a particular kind of situation,
and it involves focusing on a situation that's
kind of unrealistic, kind of artificial,
or a pair of situations that are kind of unrealistic
and kind of artificial.
But they're artificial for a reason.
They differ with respect to something
that we're interested in, a difference
that we're interested in.
And by focusing on this difference that
arises in these very simple, artificial cases,
we can learn something that we can then
reapply to more realistic, more complex cases that we actually
So let's get going.
Let's first grade hand pains in this way.
Let's say that level 11 hand pain
is the pain you get when you're wearing bullet-ant gloves.
What are bullet-ant gloves?
Well, there's a tribe in the Amazon
called the Satere-Mawe tribe that has this initiation rite.
The adolescent boys go off into the forest,
they get a bunch of bullet ants which
are large and extremely poisonous ants,
and they gather them, they drug them so
it's basically send the ants to sleep,
they insert the ants inside these woven gloves,
stingers pointing outwards.
And then as part of their initiation rite,
they have to wear these gloves for five minutes.
And to get a visceral sense of just how painful this level 11
hand pain is, I'd look it up on YouTube.
Just Google bullet-ant gloves, Satere-Mawe rite,
or just bullet-ant gloves, and it'll
take you to various videos of Westerners
attempting to do this Satere-Mawe initiation rite
and discovering just how extraordinarily painful it is.
It's very, very painful indeed.
OK, that's level 11 hand pain.
Level 1 hand pain--
say that's the kind of pain you get from a hangnail.
It's sort of uncomfortable.
It's kind of there on the fringes of your consciousness.
You sort of notice it, but it's not in any sense unbearable.
You can get on with your day.
It's a kind of nagging thing in the background of your mind.
So suppose you have to choose between one day of level
11 pain-- that's 24 full hours wearing the bullet-ant gloves.
Again, go to YouTube to get a sense
of what that would involve.
That's one choice.
The other choice-- your other option is 1,024 days--
that's 2 to the power of 10 days--
of level 1 pain.
That's around three years of a hangnail that kind of never
Again, this is where this case is
going to be a bit unrealistic.
Real hangnails, they go away after a period of time.
Or they get much worse, and they start
to bother you more and more and more.
The hangnail we're imagining remains a hangnail-level pain
for three years.
It's always there at the fringes of your consciousness, neither
getting better nor getting worse.
OK, so which would you choose, the bullet-ant
gloves or the hangnail?
I take it that, of course, you're
going to choose the hangnail.
Everybody I've asked this question to
chooses the hangnail.
Of course you're going to choose the hangnail.
Look at those bullet-ant gloves.
Never, ever would you choose such a thing.
But here's an argument to the effect
that you're wrong, that it's better for you
to take the bullet-ant gloves than it
is to take the hangnail.
OK, so the argument roughly is going to go like this.
We'll put it more precisely in a moment.
But roughly, the argument goes like this.
Start by comparing one day of level 11 pain--
that's the bullet-ant gloves--
with two days of level 10 pain.
What's level 10 pain?
Well, it's just a little bit off level 11 pain.
It's still unbearable.
It's still agony.
But it's a little bit less bad.
Which is better for you?
Which is less bad for you?
It seems like although the level 10
pain is slightly less painful, you've got twice as much of it.
So it's better for you to take the day of level 11 pain
over the two days of level 10 pain.
That's your first comparison.
Now compare the two days of level 10 pain
to four days of level 9 pain.
Again, the level 9 pain is a little bit less bad
than the level 10 pain.
But there's twice as much of it.
That might make you think, if you
had a choice between these two things,
you'd be right to choose the two days of level 10 pain
over the four days of level 9 pain.
Because it'd be better for you--
less bad for you.
And now I think you can already see where this is going.
You have to compare the four days of level 9 pain
with eight days of level 8 pain.
Again, level 8 pain, a little bit less bad.
Again, there's twice as much of it.
So on balance, that's worse.
And we go the whole way through the series--
16 days of level 7 pain, 32 days of level 6 pain,
64 days of level of 5 pain, 128 days of level 4 pain,
256 days of level 3 pain, 512 days
of level 2 pain, until we arrive at 1,024 days of level 1 pain,
and we've been continually getting worse.
Well, if each of those things is worse than its predecessor,
then the last must be worse than the first.
It must be worse that you experience 1,024 days of level
1 pain than you experience that one day of bullet-ant gloves.
OK, that was a quick version of the arguments.
Let's kind of reconstruct it in terms
of premises and conclusions.
OK, we have here your series.
Here are the series of experiences
that you might have.
Premise one of the argument says this.
Each of these experiences is worse for you
than its predecessor.
Each time you're experiencing a little bit less intense pain,
but twice as much of it.
Premise two says worse for you, the relation "worse for you,"
is a transitive relation.
That's a bit of philosophy terminology.
Let me explain what it means.
It means that for any experiences A, B, C,
if A is worse for you than B, and B is worse for you than C,
then A is worse for you than C. The conclusion of the argument,
then, is that 1,024 days of level 1 pain is worse for you
that one day of level 11 pain.
Now, that's a valid argument, I can promise you.
So if you accept the premises, then you
must expect to accept the conclusion.
It's impossible that the premises be true
and the conclusion false.
Now, you probably started off not believing the conclusion
of this argument.
But I guess you also believed the premises of the argument
before you looked at it.
And so if you accept those premises,
you've got to change your mind.
You've got to accept the conclusion.
And this is kind of amazing.
We've come to a situation where doing a bit of philosophy
has persuaded you to change your mind about something that
seemed very, very obvious to you before you started
thinking about it.