Why shouldn't we be grateful to the totality of our ancestors for getting us this far? Who is to say that we could change even a butterfly wing's flutter of the distant past and still have everything turn out as now?

b)I am specifically claiming that while "nothing means anything" is the--lie that tells the truth--summation of nihilism it, by it's very nature, doesn't imply a course of action. So it doesn't matter how metaphysical of a claim it is.

You know nothing, Jon Snow!