Aristotle's 'Metaphysics', Book I, Chp. II

In chapter 2 of Book I of the Metaphysics, Aristotle proceeds to explain that the science we're about to inquire into is this "knowledge for it's own sake" that he talked about in chapter 1. To get at just what this science is, he thinks it best to take a look at our "notions of the wise man" (since the "wise man" is the person who desires and acquires knowledge for its own sake, as described in the first chapter).

The first point Aristotle makes in this regard is that the wise man is someone who we take to "know everything". The wise man knows everything in the sense that he knows about ultimate causes and first principles; e.g. those universals which contain all the particulars which they describe. An example of this might be, say, knowing the set of all and only round objects. To know this set (the set in this case functioning as the "universal"), is to know it's individual members (each member functioning as the "particular"). And thus it is that knowledge of universals necessarily entails a knowledge of those particulars which instantiate them. As Aristotle says, "...knowledge of everything necessarily belongs to the man who more than any other has knowledge of universals, since such a man knows in a way all the individuals that are included in them".

His next point about the wise man is that we take him to know the things which are the most difficult to fully know. Aristotle says that these first principles and causes are the most difficult to know because they are furthest removed from the senses (which in themselves only give us knowledge of particulars). The assumption here is, of course, that all our knowledge first arises from the senses (Aristotle being a sort of proto-empiricist).

The third point to be made about the wise man is that we generally take him to be wise, in part, because he is the "most accurate". What he means by this is, I think, that an accurate description of any object or set of objects will only be so if it discusses their ultimate causes. He also makes the point that a science is more accurate the fewer principles it has (to illustrate this he gives the example of arithmetic being more accurate than geometry). I assume his point is something along these lines: That the more first principles, or axioms, a science takes for granted, the more likely it is to be inaccurate (I assume he's making some sort of epistemic point here, but I'm not sure). An interesting thought, I think, is that this could be a prescursor to a principle like Ockham's Razor.

Next, he makes the point that the person who desires knowledge for its own sake will have knowledge of what is "most knowable". What Aristotle means by this is that the most knowable things are those which we must assume for all other knowledge. It follows that knowledge of the most general causes and principles of the world, because they allow us to understand the less general and more specific, are "most knowable" in the sense Aristotle is using the term.

The wise man, also, will be the one who is best at giving instructions (since, as Aristotle says, the wise man should give instruction and should be instructed by no one). He says that the wise man will be best at giving instruction, even in practical matters, because of his knowledge of causes and first principles. His argument is something like this: To know the ultimate cause of something is to know its nature, to know its nature is to know its end or purpose, and to know somethings end or purpose (or its "good") is to render one capable of instructing others as to how to achieve that things end or purpose.

Aristotle ends the chapter with a discussion of the essence of philosophy. That essence, he says, is essentially unproductive. He identifies the science of "first causes and principles" with philosophy itself, or at least its summit (that being, I assume, the project of metaphysics). This fact, though, he does not take to be a defect of the project. He portrays the science as wondrous and divine. He says, "...even a man who is fond of myths is in a way a philosopher, since a myth is made up of wonders", and "...just as a free man is one who exists for his own sake and not for anyone else's, so we study this science as the only one that is free, since it is the only one that is studied for its own sake". Because it is man's nature to be in a sense enslaved, and God's nature to be essentially free, Aristotle portrays doing philosophy as "more than human", and indeed divine. He says that this science is divine on two accounts: First, the science of first causes and principles would be most fully possessed by God himself, since he is the ultimate source of cause and principle. Also, being the source of cause and principle, God himself would be the ultimate end of such a study.