Skepticism, while logically impeccable, is psychologically impossible, and there is an element of frivolous insincerity in any philosophy which pretends to accept it.
The standard argument against nihilism – the notion that life is an affair devoid of meaning – goes something like this: Nihilists don’t actually believe anything they’re saying because they still act as though the world is ordered. They still value something, like freedom from pain, and this is revealed through their actions.
The implication, then, is that nihilism is bullshit. If people believed it, they would act differently, so you need to pay no attention to nihilism, because no one really believes it anyways.
This is not a satisfying refutation. The argument relies on the notion that one’s beliefs and one’s actions need to be aligned. If Andy says that he believes your pet Burmese python, Handsome, is harmless, but is hesitant to hold him, then Andy is a fucking liar.
But that’s brain damaged. You can believe something on one level while not accepting it on another. You can believe that the odds of being attacked by a shark are nigh non-existent, but still be afraid to swim in the ocean. You can believe that you really ought to stop eating unhealthy food and keep eating it anyways. I know that the Earth is hurtling around the sun at 67,000 miles per hour, but it sure doesn’t feel like it.
The behavior of those who hold a belief doesn’t speak to the accuracy of that belief. There are a lot of stupid atheists, but that’s not evidence either way as to whether or not there is a God. There are a lot of utilitarians failing to live up to the moral standards they set for themselves, but this doesn’t mean they don’t really believe it, and whether or not someone really believes something doesn’t speak to the truth of that belief.
If humans are incapable of being perfect nihilists, this is a fact about human capabilities, not about the truth of nihilism.