Dialogue on induction

Greek Coffee

Philario was sitting in the coffee shop, typing into his computer when he saw his friend Hector and greeted him.

Philario:  Hi, Hector.  What’s up?

Hector:  Well said, Philario.  What is up.  Who is down.

Philario:  Are you trying to Costello me?

Hector:  I wasn’t Abbott to do that.

Philario:  Very funny.  I’m searching on induction.  Can you tell me what it is?

Hector:  It depends on what kind of induction you want.

Philario:  I want the kind of induction used in natural science.

Hector:  OK, say we’ve got this large urn. You put your arm in and as far as you can tell it’s full of pieces of pottery.  Then you pull out one piece, and it’s painted blue.  What do you conclude about how the other pieces are painted?

Philario:  I don’t know; they could be painted anything.  Perhaps they’re from a beautiful urn that broke in pieces.

Hector:  Now think like a natural scientist.  What do natural scientists say about nature?

Philario:  They say nature is uniform.

Hector:  So if nature is uniform, how are all the balls painted?

Philario:  They must be painted the same way.

Hector:  That’s right!  So the natural scientist says they’re all painted blue.

Philario:  But they could easily be wrong!

Hector:  Did you ever notice how often natural scientists change their opinions?  They don’t seem to worry about being wrong.

Philario:  Well, I would worry about being wrong.

Hector:  Then you’re not a natural scientist!  Now suppose you pull out another piece, and it’s also painted blue.  What do you conclude?

Philario:  There’s beginning to be a pattern.  So it’s possible they could all be painted blue.

Hector:  You need more confidence if you want to be a natural scientist.

Philario:  I didn’t say I wanted to be a natural scientist.  I just want to know how they think.

Hector:  So try thinking like one.  What do you say?

Philario:  I suppose I should say they’re all painted blue.

Hector:  Now do you have any evidence to back that up?

Philario:  I don’t have much evidence; only two pieces.

Hector:  But is there any contrary evidence?

Philario:  No, not yet.

Hector:  There’s no contrary evidence so no-one can say you’re wrong yet.

Philario:  That’s not much consolation.

Hector:  You need more confidence, my man!  You can prove your case by appealing to all the available evidence.

Philario:  But someone else might take out other pieces and find they are painted differently.

Hector:  Has that happened yet?

Philario:  No.

Hector:  So you’ve made your case for now.  No-one can prove you wrong.

Philario:  Now suppose you put your hand in and pull out another piece, and it’s painted red.  What do you say?

Hector:  I would say I was wrong about all of them being blue because some of them are red.

Philario:  That’s weak, much too weak.

Hector:  I could say based on the evidence two-thirds are probably blue and one-third are probably red.

Philario:  That’s what statisticians say!  You’re trying to think like a natural scientist.

Hector:  So what should I say?

Philario:  You should say there are two kinds of pieces in the urn.  One kind are all painted blue and the other kind are all painted red.  You might say that the blue kind are from a piece of blue pottery and the red kind are from a piece of red pottery.

Hector:  That sounds like a hypothesis.

Philario:  Yes, it is a hypothesis!

Hector:  So natural scientists make bold statements based on flimsy evidence and call them hypotheses.

Philario:  You might put it that way.  But remember they are careful not to contradict evidence, unless they want to say the evidence is erroneous.

Hector:  Why would they say evidence is erroneous?

Philario:  Because it gets in the way of a good hypothesis!

Hector:  So it’s all about making up hypotheses that sound good.

Philario:  You’re catching on!

Hector:  I think I’m too cautious to be much good at that.

Philario:  Have you considered becoming a statistician?

Hector:  No, do they like to be cautious?

Philario:  Boy, do they like to be cautious!  That’s probably all they do.

Hector:  They must eat sometimes.

Philario:  Probably.  But you can’t be 100% certain.

Hector:  I think I can be 100% certain about some things.

Philario:  Like what?

Hector:  I can be 100% certain that the sun will rise tomorrow.

Philario:  OK, let’s consider that.  What do you base that assertion on?

Hector:  I base it on the fact that it’s risen every time in the past.

Philario:  I didn’t know you were as old as time!

Hector:  Well, I haven’t personally witnessed the sun rising every day, but someone has.

Philario:  Who has?

Hector:  Other people.  There are records that go back to Babylon.

Philario:  What about before Babylon?

Hector:  Well, I suppose it must have risen before that, too.  We’ve got thousands of years’ worth of evidence that the sun rises every day.

Philario:  So there’s a high probably the sun will rise tomorrow.

Hector:  That’s what I said!

Philario:  No, you said you were 100% certain the sun will rise tomorrow.

Hector:  That’s virtually the same thing.  You’re not going to split hairs, are you?

Philario:  Of course I am!  We’re thinking like statisticians now.

Hector:  Oh no.  You mean statisticians are super cautious?

Philario:  Professionally, yes.  They’re paid to be hedge their bets.

Hector:  I don’t think I’m cut out to be a statistician either.

Philario:  You could always be a philosopher.

Hector:  Why is that?

Philario:  They can take any side of an argument!

Hector:  I think you’re better at that than I am.

Philario:  Study philosophy and you’ll get better at it.

Hector:  I’d rather have a latte.