Monday, March 02, 2009

Maddy's Second Philosophy: I.2 Neo-Cartesian skepticism

The Descartes we met in the first section is a methodologist of science with a bad idea about how to improve our scientific success rate. He isn't so very far removed, then, from the Second Philosopher in terms of his general intellectual concerns. She can warmly approve of this Descartes's overall aim of doing science better: she just rejects his failed attempt at securing that aim.

But there's another Descartes (a fictional figure perhaps, but occupying a familiar location on the philosophical landscape). To quote Stroud,

By the end of his First Meditation, [this] Descartes finds that he has no good reason to believe anything about the world around him and therefore that he can know nothing of the external world.
For this Descartes -- or better, for the 'neo-Cartesian sceptic' -- doubt has become more-than-merely methodological. He is not just setting aside received but fallible beliefs about the world, reasonable and unreasonable alike, to locate an indubitable residue: he thinks he has an argument that even the most 'reasonable' received beliefs in fact just aren't reasonable. How does the naturalistically inclined philosopher respond?

Now, speaking for myself, I'm all for a cheerfully resolute response. We have every good reason to suppose that in ordinary life, when our usual criteria indicate that we are wide awake and not dreaming, we are wide awake and not dreaming. And if the sceptic asks me how I rule out the possibility that, for all that, my whole ordinary life is in fact just one big coherent dream (unlike any ordinary dream, of course, a put-up job engineered by an evil demon), I just riposte that I have been given not the slightest reason that to suppose that that is a live possibility. It is one thing to use the evil demon fantasy as Maddy's Descartes does, as an imaginative tool in trying to locate some core of infallible beliefs: it is something else entirely to imagine that the honest enquirer needs to rule out the evil demon scenario before he can regard science as a reasonable enterprise. The scientist just doesn't have to waste her time ruling out myriads of daft hypotheses she hasn't the slightest reason to suppose are true. And for me, pretty much end of story.

Speaking for her Second Philosopher, Maddy is rather more patient in tangling with the neo-Cartesian sceptic (though whether the sceptic will appreciate her efforts is a moot question). I won't go into all the ins and outs. She agrees, of course, that "she can’t justify anything without appeal to her familiar beliefs and methods", but so what? Ah, says Stroud,
... in philosophy we want to understand how any knowledge of an independent world is gained on any of the occasions on which knowledge of the world is gained through sense-perception. So, unlike ... everyday cases, when we understand the particular case in the way we must understand it for philosophical purposes, we cannot appeal to some piece of knowledge we think we have already got about an independent world. [My emphasis]
So now, as Maddy puts it, "it's freely admitted that the skeptic is engaged in a peculiarly philosophical project, distinct from mundane concerns". But what notion of 'philosophy' is in play here? I for one just haven't much grip on what sort of coherent project might be meant here, this special 'philosophical' enquiry that isn't part of science broadly conceived. Maddy offers the following from Stroud:
All of my knowledge of the external world is supposed to have been brought into question in one fell swoop ... I am to focus on my relation to the whole body of beliefs which I take to be knowledge of the external world and to ask, from 'outside' as it were ... whether and how I know it ...
But that gives the game away. If the 'philosophical' project is supposed to involve jumping outside my beliefs and methods, and trying to squint sideways at them from 'outside' as it were, to see how they match up to an external world, then that is just incoherent. (If the sceptic is complaining that the project can't be pulled off, then he's quite right the project is impossible, but quite wrong to complain.)

Maddy puts it this way,
Our Second Philosopher freely acknowledges one poignant aspect of the human condition: we can't step outside our system of beliefs and methods and justify them from an external perspective; the only perspective we can occupy is our own.
But why is that particularly 'poignant'? -- (dictionary: 'evoking a keen sense of sadness or regret'). You can't have a settled feeling of regret that you can't be both 'inside' and 'outside' your own thoughts (thinking them, but squinting at them sideways too) any more than you can sensibly regret that two and two isn't five, or regret that you can't back and kill your own grandfather before he sired your parent. Stroud himself talks of
the desire to get outside that knowledge and that condition, as it were, while somehow retaining all the resources needed to see them as they are.
But again, that is just an incoherent aspiration. And if it is a persistent aspiration, then that just means that it's a bit of intellectual bindweed, and the Second Philosopher shouldn't feel any sadness or regret about resolutely taking the flame-thrower to it.

6 comments:

a.c. said...

"You can no more be sad that you can't be both 'inside' and 'outside' your own thoughts (thinking them, but squinting at them sideways too) than you can be sad that two and two isn't five, or sad you can't go back and kill your own grandfather."

Someone can be sad, and some even are sad, that they can't go back and do more -- more than they actually did -- for someone who has died.

So perhaps it's the (physical? logical?) impossibility of killing your own grandfather that's the problem? Presumably you could kill him after he'd fathered your mother or father (whichever it was). Maybe that's not impossible enough. So let's suppose we're talking about killing him before that.

And let's suppose there was some good reason for wanting to kill him. Perhaps he was the cause of much suffering.

I think someone could be sad that that wasn't possible.

Though if poignance is what's desired, a different example might be more suitable.

Peter Smith said...

Yes, maybe I over-did it! I've slightly toned down the remark. What I was trying to get across was the oddity of finding it poignant that we can't do something which it is incoherent to suppose that we could do. Not that a great deal hangs on this: but that Maddy wrote that way suggested (to me at any rate) that was being a bit too concessive to Stroud's way of thinking about the neo-Cartesian sceptic.

Ezra Cook said...

"Now, speaking for myself, I'm all for a cheerfully resolute response. We have every good reason to suppose that in ordinary life, when our usual criteria indicate that we are wide awake and not dreaming, we are wide awake and not dreaming. And if the sceptic asks me how I rule out the possibility that, for all that, my whole ordinary life is in fact just one big coherent dream (unlike any ordinary dream, of course, a put-up job engineered by an evil demon), I just riposte that I have been given not the slightest reason that to suppose that that is a live possibility."

It would seem to follow, from this line of thought, that (1) if a table in front of you appears red to you, you have an indication that this table is red, and (2) if you have an indication that the table is red from some reliable process (say, perception), then you know the table is red. There is no need here to add a third condition that you must know that said process is reliable (as that would make the skeptical scenario salient). Given this, however, and accepting that knowledge is closed under known implication (or the weaker position-to-know closure, either suffices), you are going to be stuck accepting instances of so-called easy knowledge. For example:

"Suppose my son wants to buy a red table for his room. We go in the store and I say, 'That table is red. I'll buy it for you." Having inherited his father's obsessive personality, he worries, 'Daddy, what if it's white with red lights shining on it?' I reply, 'Don't worry--you see, it looks red, so it is red, so it's not white but illuminated by red lights.'" (Cohen, "Basic Knowledge and the Problem of Easy Knowledge", Philosophy and Phenomenological Research 2002)

This line of reasoning is valid, given (1), (2), and closure, but it does not seem correct that we can reason in this way without first examining our surroundings for red lights and the like.

Peter Smith said...

We all know that in certain cases, colour-judgements need to be checked for lighting conditions (that's why we e.g. take curtain fabric samples out into the daylight). Any sensible version of reliabilism will have to factor that in. But I'm not really sure I follow the relevance of this, as my quoted remark doesn't actually commit me to reliabilism.

Ezra said...

"when our usual criteria indicate that we are wide awake and not dreaming"

What are usual criteria if not reliable processes operating in relevant conditions? I took this to be a Sosa style response, which is committed to a reliabilism at the level of basic (or "animal") knowledge.

The point of the argument is exactly that "We all know that in certain cases, colour-judgements need to be checked for lighting conditions", and yet anyone who takes a Moorean stance regarding basic knowledge seems to be able to reason sufficiently without said checking. It is a problem for reliabilism and a very large number of related theories in contemporary Epistemology, and one that is currently gaining some traction in contemporary debate (as evidenced by a recent article in PhilStudies and the final chapter of Sosa's new book).

james said...

I enjoy living as a skeptic, in the original Sextus Empiricus mode. I seem to get by pretty well without the need for certainty. I cultivate a lack of commitment to any belief about reality, while still playfully entertaining those beliefs. When I see a philosopher dismiss skepticism as you appear to be doing, I wonder what must be motivating him. Is philosophy for some people the need to be able to say what is true and not true? That is such a vain and impossible project.

Try accepting the skeptic's warnings that we can't know what is so, and witness how it opens your mind.

In any case, as a professional software tester, I have learned I cannot depend on any natural fact. If I seem to depend on one, now and again, it's just a sign of my infirmity as a thinker. Indeed, in computing, Descarte's Demon works every day to fool me. I don't believe tables are red, I don't need to believe. I say "the table appears red to me." Belief is a luxury of the non-philosopher/non-tester.