The sentence you quote is the first step in the most fully-stated version of Gorgias’ skeptical argument, designed to demonstrate that nothing exists or, at least, that the concept of existence is nonsense. It has a logical form something like this: 'If it is the case that A is a meaningful concept, then we must be able to say one of the following: either something is A, is not-A, or is both A and not-A.' This isn’t that far away from ‘If Chelsea play a football match, then either they will win, lose or draw’. If it can be shown that Chelsea neither won, nor lost, nor drew, then it can be concluded that they did not actually play a game at all. As such, the argument is a pretty straight-forward reductio ad absurdum . The argument against each of the three possibilities is interesting, I think, mainly for the discussion of infinity and creation. These discussions were commonplace in Greek philosophy subsequently and, indeed, they are strikingly like the dialectical arguments Kant analyses...

As always with Nietzsche the context needs to be reconstructed. The passage as a whole is addressed to physicians, but the claim you quote is addressed to ‘pessimists’; to those who would renounce life and its values, while continuing to live . Nietzsche is simply asking such pessimists to take seriously their own position. However, we shouldn’t miss the irony of the last phrase: ‘one almost earns the right to live’. Pessimism, on Nietzsche’s analysis, is actually a kind of perverse clinging to life, defending one’s mode of life. So, to be capable of ending it would also mean to not be a pessimist. It would be a contradiction in act. To my mind, the dominant idea in this section, and a beautiful one at that, is the notion of ‘death at the right time’, earlier. This is an affirmation of a generalised suicide, of ‘death chosen freely …[that] makes it possible to have a real leave-taking’. He contrasts this with a Christian attitude towards death, as the last chance to repent, as the...

An excellent question. There are two ways of answering this. First, historically, a philosopher like Sartre developed over his long career, and the ‘pure’ existentialism that he espoused in the 1940s is greatly modified in the political thinking of the 1950s and later. However, this is probably not a very interesting answer. I mention it only because sometimes we can fall into the trap of asking ‘what does Sartre (or Kant, or whoever) say about X?’ without specifying which Sartre or Kant. A more interesting answer concerns the type of political, psychological and social illusions that go, it is argued, hand in hand with capitalism, and which are dispelled by socialism or communism. Insofar as existentialism develops a metaphysics of the true nature of reality, of the self, and of social relations between selves, then an authentic existence would be one that implicitly or explicitly, recognises these truths and in particular does not take a falsehood as an excuse for abdicating...

See the note to page 122 of An Enquiry Concerning Human Understanding. He writes '...the arguments admit of no answer and produce no conviction.' The point is not quite what you take it to be. Hume is considering the nature of scepticism (here he considers Berkeley to be a sceptic), and he claims it to be perfectly possible rationally but perfectly impossible psychologically. 'Conviction' is a psychological claim, about what I expect to happen next, for example. Your notion of bigotry is interesting. Why is Hume not just being stubborn, even pig-headed? Broadly speaking, it is because he believes that reason, on its own, is quite useless. Its purpose is to help us analyse our experiences, and modify our beliefs on that basis. Reason, for Hume, serves experience and the psychology of conviction, rather than the other way around. Since he is always happy to look at new empirical evidence, he certainly hasn’t got the closed mind of a bigot. It’s just that he has no truck with the...

The quote is from Twilight of the Idols , first section, and not quite accurate but close enough. To be sure, Nietzsche was not afraid to exaggerate, when he could get some rhetorical mileage out of it. Here, his point is not unrelated to the Darwinian idea that competition among species means that only those species or variants that are best adapted will survive. In the case of human beings, Nietzsche argues, I can change my way of life, habits, and so forth -- and these changes make me stronger in the sense that I am able to out-compete other humans (taking ‘compete’ in as broad a sense as possible). (Significantly, the same reasoning applies to groups of people with respect to other groups.) His point is supplemented by the observation that generally among animals (and, he would claim, among earlier human societies) the sick are not protected and cared for as we believe is just today. For a gazelle, say, being weakened is essentially the same as being dead. Today, we tend to think of this...

This is a larger question than it appears. It goes to the heart of what philosophy is or should be. That is, what methods should be employed, what standards or virtues of expression, language, analysis or argumentation, what subject matters are philosophical, and so forth. Heidegger is an important figure in what is sometimes called 'Continental' or 'European' philosophy. (Unfortunate names, but the ones most widely used). There are thousands of highly educated, widely published and read, and very distinguished philosophers who are working in this 'tradition'. Many of them disagree strongly with Heidegger, but at least take him seriously. However, there are, equally, thousands of philosophers of equal stature who either consider him to be incompetent as a philosopher, or just not philosophical at all. I cannot answer your question, therefore. I can only advise you to read commentators who condemn Heidegger, and likewise commentators who take him seriously, whilst bearing in mind that what is...