For instance, in the Daodejing, the Chinese challenge to the rationalism of Confucianism, the ideal is not reason but an effortless spontaneity, the Dao, the Way of life. Everything is downhill from the Way.
When the way is lost, virtue appears; when virtue is lost, kindness appears; when kindness is lost, justice appears.And, one might suspect, when justice is lost, then power appears.
Something similar appears in the West with the Romantic rebellion, a reaction against the totalitarian idea that Reason is everything.
In the Ethics, Aristotle hangs his hat on reason, that "the function of man is an activity of soul [anima] which follows or implies a rational principle," and a good rational principle, well executed, at that.
[H]uman good turns out to be activity of soul in accordance with virtue, and if there are more than one virtues, in accordance with the best and most complete.This would add up to happiness (i.e. eudaimonia, which translates as human flourishing) and that in a complete life.
At the beginning of the Ethics, Aristotle tells us what all this is leading to: the highest good, as in managing the relations between men in the polis. Here he establishes that the highest good is the combination of subsidiary goods, as the skill of harness-making is subsidiary to horsemanship, and horsemanship subsidiary to strategy, and strategy to politics. And the highest good is clearly politics,
since politics uses the rest of the sciences... it legislates as to what we are to do and what we are to abstain from... this end must be the good of man.But in Ethics X 8, Aristotle backs up a bit, and, once he has dealt with mere pleasure, and established "happiness is activity in accordance with virtue," he discovers that the highest form of happiness is found in "the man who is contemplating the truth", for he doesn't need money like the liberal man, or power like the brave man. "[F]or deeds many things are needed" but not for the contemplative life.
Anyway, says Aristotle, the contemplative life is much like the life of the gods, for it is ridiculous to imagine them running around doing absurd things like dispensing justice, signing contracts, or confronting dangers. No, "Happiness, therefore, must be some form of contemplation." The gods must "delight in what was best and most akin to them (i.e. reason)" in other words, philosophers, and "the philosopher will more than any other be happy."
This is straying rather far from the simple function argument, that happiness is virtuous action according to a rational principle, and that, moreover, the highest and best form of the good is political science and legislating the good of the polis.
In fact, if you think of philosophy as getting close to the gods, then it must be getting close to some kind of ineffable, effortless spontaneity. Which is what the non-rational Daodejing was proposing about the same time, only thousands of miles away in China.