Aristotle on Metaphysics(2004) - Bibotu.com

THE DEFENCE OF PNC 127So he argues that these are the views that one must defend if one wants todeny PNC. But he thinks that there are thinkers—in particularProtagoras, Heracleitus and their followers—who defend these views, andso deny PNC. We may call these thinkers, as <strong>Aristotle</strong> characterizes them:phenomenalists and relativists. (But we will need to consider the exactsense of ‘phenomenalism’ and ‘relativism’ here.) The ultimate challengethat <strong>Aristotle</strong> sets himself is, therefore, to respond to these thinkers andthese views (i.e. 1–4). For he will argue (in IV. 5–6) that PNC is indeedtrue of the things themselves and of things without qualification; it is notonly true of things as they appear to us and as we conceive them.We will consider <strong>Aristotle</strong>’s first two aims (i.e. A and B) in this chapter;and his third aim (C), i.e. the response to phenomenalism and relativism,in the next chapter.There is, however, also a single overall aim to <strong>Aristotle</strong>’s defence of PNC.In book III, the book of aporiai, he raised the following aporia: Is it the taskof a single science to investigate both the ultimate principles of being and thebasic principles of reasoning (e.g, the principle of non-contradiction)? Or is thisthe task of fundamentally different sciences? (see the second aporia, 996 b 26–997 a 15). The question in this aporia is how metaphysics, i.e. the science ofthe nature of being, is related to logic, i.e. the science of the basicprinciples of reasoning and rational thought (e.g. the principle of noncontradiction).Does metaphysics include logic or is logic independent ofmetaphysics? And, if the latter is the case, is logic perhaps morefundamental than metaphysics? But <strong>Aristotle</strong> will argue (in IV. 3) thatmetaphysics as it was characterized at the opening of book IV, i.e. as thescience of all beings and of beings simply in so far as they are beings,includes logic, i.e. the science of the basic principles of reasoning andrational thought. For he will argue that in particular PNC, which is acentral principle of reasoning and rational thought, is true of things, and itis true of things simply in so far as they are beings—things that are. So thisis how he answers this fundamental aporia about the relation betweenmetaphysics and logic.It is important from the start to emphasize this central overall aim of<strong>Aristotle</strong>’s defence of PNC, i.e. the aim of arguing that PNC is true not onlyand not primarily with regard to reasoning and rational thought (i.e. PNCis not only and not primarily a logical principle), but is true with regard tothings and things simply in so far as they are beings (i.e. PNC is ametaphysical principle). A large part of his defence of PNC may suggestthat he wants to defend PNC only, or primarily, as a logical principle, i.e.a principle that is only, or primarily, about the nature of reasoning andrational thought. This may be suggested by his aim of arguing (in IV. 3)