I have actually checked it now, Aristotle speaks in that passage about ethics - well, the subject of the treatise at hand - which he characterizes as 'a kind of political science.' Hence, it is hopefully not incompatible with my suggestion that he means political arguments which, as suggested in the Rhetoric, he does not hold to possess demonstrative certainty. But presumably ethical arguments would be held to be similar to political. Also, hopefully it should not be taken that I necessarily hold the same opinion with Aristotle, he was cited as an authority so I tried to see what he might he might have meant. O.K. On Saturday, January 25, 2014 9:55 PM, Robert Paul <rpaul@xxxxxxxx> wrote: While discussing a passage from Whitehead John McCreery wrote I am particularly struck by that line, The kind of necessity proper to mathematical demonstrations cannot be transferred to philosophy, which instantly reminds me of that favourite passage of mine in the Nichomachean Ethics, the knowledge of which I owe to Robert Paul, in which the Sage observes that not all arguments are equally susceptible to mathematical rigour and that it is the mark of an education person to know which is which. *Omar is troubled by this. He writes I am pretty sure that Aristotle would not have agreed with the above. He would have thought that many philosophical arguments are capable of demonstration that carries just as much necessity as mathematical demonstration. When he speaks of arguments which are not capable of demonstration he is most likely thinking of political and legal arguments, which he transfers to the subordinate realm of rhetoric. Our discussion will be adequate if it has as much clearness as the subject-matter admits of, for precision is not to be sought for alike in all discussions, any more than in all the products of the crafts. Now fine and just actions, which political science investigates, admit of much variety and fluctuation of opinion, so that they may be thought to exist only by convention, and not by nature. And goods also give rise to a similar fluctuation because they bring harm to many people; for before now men have been undone by reason of their wealth, and others by reason of their courage. We must be content, then, in speaking of such subjects and with such premisses to indicate the truth roughly and in outline, and in speaking about things which are only for the most part true and with premisses of the same kind to reach conclusions that are no better. In the same spirit, therefore, should each type of statement be received; for it is the mark of an educated man to look for precision in each class of things just so far as the nature of the subject admits; it is [clearly/surely/plainly] equally foolish to accept probable reasoning from a mathematician and to demand from a rhetorician scientific proofs.[Nicomachean Ethics, I.1] <http://classics.mit.edu/Aristotle/nicomachaen.1.i.html> *Here, Aristotle doesn't appear to talk so much about philosophical arguments, as about our discussions of different subject matter: they shouldn't all be considered in the same way. (I'm not sure just what a philosophical argument is, unless it's the sort of thing people engaged in at Plato's Academy, and now engage in in the pages of Mind, The Philosophical Review, and elsewhere.) The most important line in this passage from the NE is the last. I'm glad John remembers it. RP