Of what can we be certain?
There’s a few different answers to this question. Some would say that we can be certain of nothing – this is the more radical position. It pertains to everything – moral judgement, ethical judgement, the whole shebang. You can’t really be certain of anything. This seems to me to be somewhat self-refuting – can you be certain that there is nothing you can be certain about? If that’s the case, then it seems like it cuts its own feet out from under it.
But let’s take the more radical line: we can’t even be certain that there’s nothing we can’t be certain about. Radical skepticism like this seems to lead to simply absurd and incoherent conclusions – we can’t be certain that we can’t be certain, on for infinity. So this seems to me to be a somewhat incoherent picture.
So much for radical skepticism, then. How else can we know of what we can be certain?
Well, we can be certain in mathematics – indeed, mathematics is home to a very special certainty: the certainty of 2+2=4. This is as rock-bottom certain as one can be – mathematical certainty. But we can’t be that certain about other things – because other things aren’t mathematics.
It seems to me, however, that we can be reasonably certain of certain things – I’m certain that I love my fiance, and that she loves me. I’m certain that I love a good dark German ale, but don’t like bitter IPA’s. I’m certain that there are other people, that gas is expensive, and lots of other things – and I’m reasonably certain other people are certain about these kinds of things as well. It would seem in that case that what I’ll call ‘common sense certainty’ is the best position – radical skepticism seems to be unwarranted. It is unreasonable to suppose that people aren’t really there, or that any of the things I just listed aren’t certain enough for me to be justified in believing them – they seem perfectly warranted beliefs. In fact, to not believe any of these things would be the irrational position to take. This is related somewhat to the idea of ‘properly basic beliefs’ – and it seems to me that such beliefs provide a good grounding for a common-sense certainty.
There is a sense in which, as stated above, one cannot be certain in the mathematical sense of any of those things – perhaps I’m mentally ill, having a hallucination, or any other possible circumstance that would impede my cognitive faculties. Again, however, common-sense certainty seems to me to be adequate grounds for not assuming any of those things. On this view, to posit skepticism beyond necessity is superfluous. Of course I could be under a cognitive-faculty hindering influence, but unless it was something that effected my entire being, I find it easy to imagine that there would be some sign that I was in fact suffering from such a condition.
Without reverting to foundationalism, it seems that common-sense certainty coupled with properly basic beliefs provides adequate grounds to refute radical skepticism in light of the fact that mathematical certainty is not availible for any and all beliefs.