Reliable Intuitions: Some New Thoughts on Scepticism
Recently in debate I appealed to basic intuitions as supplying certain grounds for realism about the external world. Such intuitions are best described by this thought: “of course there’s an external world—it’s just common sense!” I’ve always been slightly uncomfortable in defending this, because of a common objection, to the effect that much that was once common sense has been superseded by expanding scientific knowledge. The existence of the world is just one intuition among many, and there is no reason to think it is any more inviolable than, say, the common-sense belief (as it presumably once was) that the Earth is the centre of the universe.
But there is a world of difference (literally) between these two propositions. Not all intuitions are equal. Regarding the geocentric model, and its counterpart intuition, it was possible to investigate what the sun and planets were really doing, when this became an issue for people. Indeed, the intuition only became a model at all when there was a question as to what the real structure of the universe might be. What would it be for the very existence of the world to become an issue, outside of philosophy?
What counts here is whether things matter to people in ordinary life or in science, and the existence of an independent world can surely never become an issue here, because all life and scientific enquiry presupposes it. It is as certain as anything can be, and any doubt about it is either affected or psychotic. Just because we can imagine something’s not being the case doesn’t mean it makes any sense to doubt it. It is against the background of a real world of things and people that doubt and error get their sense, which is why the super-doubts of solipsism, idealism and global scepticism are literally nonsense.
There is nothing we do or say that does not presuppose the existence of an independent world, and its non-existence is proposed as a possibility only by historical accident, i.e., from the point of view of the Cartesian inner-outer dichotomy, with the help of an implied private language. In ditching this paradigm we do not, it is true, defeat scepticism and idealism head-on, but that is only because indulging those arguments commits us to the same paradigm, and because anything we might say in reply will also be nonsense (”I know that here is a hand”).
But there is much more to this. One thing I don’t have the knowledge for is an examination of how the status of science seems to have led quite naturally, hand-in-hand with the Cartesian-Kantian tradition, to the idea that science reveals how things really are, superseding all of our intuitions. There’s no such thing as love, free will is an illusion, consciousness does not exist, and so on. There’s a deep confusion here—or is it a confusion? Perhaps science makes it inevitable. The thought occurs to me that we cannot resist reifying the abstractions of science, so that the models begin to pollute our everyday being-in-the-world—our everyday understanding. Heidegger is the way to go here: nature as unintelligible.
Also I should emphasize the fact that, in the end, we have no choice but to rely on our intuitions; justification must eventually come to an end. All chains of reasoning must eventually end in premises which are not themselves the result of argument. We just cannot give up such intuitions as causation and the law of non-contradiction. They, and many others, form the basis on which we think, and all further enquiry must answer finally to them. But how can we draw the line between these indubitable intuitions and those that might be overturned by science? Unfortunately, it looks like there is no sharp dividing line. This may be what Wittgenstein means here in On Certainty:
96. It might be imagined that some propositions, of the form of empirical propositions, were hardened and functioned as channels for such empirical propositions as were not hardened but fluid; and that this relation altered with time, in that fluid propositions hardened, and hard ones became fluid.
97. The mythology may change back into a state of flux; the riverbed of thoughts may shift. But I distinguish between the movements of the waters on the riverbed and the shift of the bed itself; though there is not a sharp division of the one from the other.
But it might even be wrong to talk about intuitions at all, and I think it is certainly misleading to talk of them as forming a foundation of beliefs on which we can build. What we presuppose shows itself in our actions, outside of our language-games. It is not as if we have a common-sense opinion that “there is an external world”, and build everything on top of that. There is just never any question of it, and we must feebly grab at the term “intuition” only when pressed on the point by annoying epistemologists.
The upshot is that sometimes we must rely on common sense, and in daily life this is obvious. Though it sometimes goes wrong, it is more often than not a very good guide, and we should at least demand good reasons for questioning it. Such reasons in support of sceptical hypotheses have never been forthcoming.
Wittgenstein, L., ed. G. E. M. Anscombe, G. H. von Wright, 1969: On Certainty, Harper & Row