(Something I try to understand at the moment in wake of reading some Christian Apologetics stuff) If we say: - We should not impose moral judgements on other cultures. - 'Reality' is unknowable / There are noumena. - There is an 'unseen.' - Science is the only way to ascertain truth. - "Whereof one cannot speak, thereof one must be silent." - I cannot think the unthinkable. - God is unknowable. - Events are random and not connected. etc... These appear to be instances of self-defeating arguments. That is, they are contradictory in the same way as a sentence that states 'there are no objective truths' (while itself posing as an objective truth). If we say, for example, 'events are not connected,' we imply by that judgement a level of connection allowing us to reach the conclusion. If we say, with Kant, that there is a unreachable 'noumenal' (thing-in-itself) reality behind appearance, are we again making a self-defeating argument in that we are making statements about what we claim is unreachable? I am suspicious that it is really so absurdly easy to dismiss thinkers as diverse as Wittgenstein, Hume, Heidegger, Kant et al. Has anyone else thought on this issue? I am half sure I must be missing something either in way of thinking or method.