Re: A solution to the 'grue' paradox?

["Matthew Hodgetts" <matthew.hodgetts@gmail.com>]

Nick (Dippie):

 

No one's trying to say that what I have called the lison inference is valid! No one's trying to say that the lion inference is invalid! As philosophers we're just trying to find out WHY this is the case! We're trying to come to a greater understanding of things that we already believe, and that surely is a legitimate goal of philosophy.

 

The whole point of the grue paradox is to show that our understanding of induction is incomplete. Whereas before we thought that an inductive inference of the form 'I have always seen As do B therefore in the future other As will do B' was OK, the grue problem, and the other Nick's lison problem show that this isnt't a correct analysis of justified inductive arguments. Why not? Because we have a counterexample: "All the lisons I have seen are carnivores therefore future lisons will be carnivores." We're not trying to advocate that this is a correct inference. Quite the reverse. Since it is in fact fallacious and yet fits the pattern of OK inferences, it shows that our pattern for 'OK inferences' is not actually OK. We thus need further work on our understanding of induction, which is what the other Nick was trying to do.

 

Finally, you say that "'lisons' have never existed,nor (probably) will they." Well this seems to me to be just plain false. To be a lison you don't need to be a lion before 2007 and then in 2007 magically morph into a bison. No, to be a lison you just need to be in the extension of "lison": namely be a lion before 2007 or a bison afterwards. It is quite possible that a lion will live from 2000 to 2015 say, (I have no idea what the actual lifespan of a lion is). In this case the lion will only be a lison until 2007. Thus for its entire life it will be a lion, but for (about) half, the first half, it will be a lison. In 2007 it will cease to be a lison, but it will cease to be lison. There need be nothing mysterious about this creature ceasing to be a lison even though, keeping an eye on it through the night of 31st Dec 2006 to 1st Jan 2007 nothing seems to change. When I ceased to be a legal minor on my 18th birthday there were no physical changes in me. Nevertheless whilst I continued to be a human I ceased to be a minor, in fact I also became a legal major.

 

Matt

 

On 11/04/06, Nick Dippie <nd603@soton.ac.uk> wrote:

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how about the irrelephilos - a philosophical argument that seems to have
meaning now, but won't tomorrow. this can work for any argument, at any
time. there is no reason why it won't work tomorrow, it just won't seem
very interesting any more.prove to me that any of our arguments (especially
mine) don't fit this definition.provide any definition of this sort and
induction struggles to prove its wrong.

seriously though, this is exactly the kind of speculative philosophical
theorising that really gets on my nerves. no offence meant to you nick, you
didn't invent this problem, and sadly there is a long history of similar
disscussions/attempts to solve these kinds of issues.the thing is, they
don't really exist (outside of our minds that is).

the problem of induction is a geniune one, but attempting to show that it
can never be solved by creating imaginary definitions and claiming that
they prove we can never be sure is just plain silly. we base our
predictions on future behaviour of known/unknown lions on evidence we have
gained about the previous behaviour of lions. 'lisons' have never existed,
nor (probably) will they. the same goes for grue. there is no evidence for
them. their existence is purely theoretical.if there was the slightest
possibility they were possible, the whole point of the grue argument falls
down.

which is the point of it i know.to get a logically implausible idea and try
and show that one of the main tenets of our belief system can't disprove
it. the only way i can see to solve it is to re-define induction as 'there
is significant evidence this has happened in the past, therefore it will
probably happen in the future.' there is no evidence for grue, or for
lisons. therefore no argument from induction can claim there is a basis for
believing in them.

argh.i've just gotten involved in this. which is annoying, cos its not a
real issue in my mind, just philosophers trying to outdo each other in a
battle of logical proofs.(which is probably why i couldn't resist saying
something)

apologies for this being more a rant than an actual considerate answer nick,
but this is whole school/issue of philosophy seems to me to be quite
self-indulgent, technical and in-house to philosophy. i like the issues
that interest people outside of philosophy, not just those within it.

it also amuses me to have the first 2 contributors to an issue being called
nick.

cheers,
nick







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