He never addresses why a given purpose is the chief purpose, only that some intermediate goals are intended to further other goals.
I'm not sure I understand what you think the gap in his argument is (which is not to say it's not gappy). In I.7 he says specifically that human beings have a variety of aims and activities, but that a life in accordance with reason is the chief aim because it's the activity we pick out when we say someone is a good human being (as opposed to a good carpenter). So adresses, if inconclusively, the question 'Why is this our chief aim?' by pointing out that when we call a carpenter good, we mean that he's good at the activity of carpentry...in other words, the thing we picked out when we called him a 'carpenter'. In ethics, we're concerned with being a good human, so what activity do we pick out when we call someone simply a 'human'? Well, no one calls someone a good human being (in the ethical sense) for metabolizing or running well. We call them good for leading a life of reason and virtue. That's why a life of virtue is our chief aim: it's what we're good at when we're good at being human.
Also note that the whole run of I.7 has a hypothetical, provisional sort of character. He's clear that he thinks this whole 'chief aim of human life' thing is a serious and difficult problem. I.7 isn't a great argument, but he is at least taking the problem seriously.
To be honest, every time I try to read Aristotle, I end up drawing a triangular diagram and labeling the three points 'agape', 'hatred', and 'apathy', (in response to every time he uses the concept of "contraries"), and the fundamental theorem of calculus, if I'm reading the Physics.
I think a triangular diagram will be misleading in understanding Aristotle's theory of contrariety. A better one might be a continuous line, with a positive end and a negative end. Every value on the line is always expressed as a predicate of some subject characteristic of the contrariety. So the range of color, has as its characteristic substratum 'surface', and every color value on the line is predicated of a surface.
didn't peruse the entire NE to see if he addresses every possible answer, because I know well enough that "it will be evident that" his pet reason will be the One True Answer, and he will not address in enough detail why that is evident.
'It is evident that' is often a translation of a more colloquial and less committal segway. Aristotle's Greek diction, however horrible, is never as pompous as translations make it out to be.
...I'm not sure I understand what you think the gap in his argument is (which is not to say it's not gappy). In I.7 he says specifically that human beings have a variety of aims and activities, but that a life in accordance with reason is the chief aim because it's the activity we pick out when we say someone is a good human being (as opposed to a good carpenter). So adresses, if inconclusively, the question 'Why is this our chief aim?' by pointing out that when we call a carpenter good, we mean that he's good at the activity of carpentry...in other words, t
Today's post, Three Fallacies of Teleology was originally published on 25 August 2008. A summary (taken from the LW wiki):
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