I am only quoting. There are other animals as well.
You can’t compare the two, because Nietzsche was a hedgehog and Foucault was a fox.
Isaiah Berlin said that there are two kinds of thinkers:
“There is a line among the fragments of the Greek poet Archilochus which says: “The fox knows many things, but the hedgehog knows one big thing.”
[T]he words … mark one of the deepest differences which divide writers and thinkers, and, it may be, human beings in general. For there exists a great chasm between those, on one side, who relate everything to … a single, universal, organising principle in terms of which alone all that they are and say has significance – and, on the other side, those who pursue many ends, often unrelated and even contradictory….” [Isaiah Berlin, The Hedgehog and the Fox, 1953.]
Nietzsche had one Big Idea: that the West was wrong to think that human beings are at their best when they are using their reason to reflect on their beliefs and desires, trying to determine whether their beliefs are true or false and whether their desires are good or bad, and pursuing what they discover to be universally true and good.
In reality, he thought, we’re at our best when we’re behaving spontaneously or instinctively, i.e. exercising some complex skill without consciously thinking about it, just reveling in the sheer joy of being alive and growing into something unknown and original.
Nietzsche tried to re-think everything in terms of this idea. He was a hedgehog.
Foucault, on the other hand, was always changing his mind about what mattered. He started out as an historian of science concerned with “soft” sciences such as psychology and psychiatry, and eventually extended his interest to the history of the human sciences as a whole. At the same time, he developed a deep interest in modernist literature, which he dropped after a while in favor of politics. He shifted to topics related to the growth of the modern state from the 18th century on, which led him by a circuitous route to questions of subjectivity.
Throughout all of this he connected his thoughts to a variety of disciplines, from history to literature to philosophy to political science and sociology to cultural criticism.
This isn’t to say that Foucault didn’t have some enduring values and intuitions that guided his researches. He believed that it was important to identify and describe what he took to be a form of oppression that was peculiar to modernity: the ways in which individuals, by accepting a certain picture of the world deriving from “human sciences” such as sociology concerning what is normal – a picture that is allegedly grounded in empirical, scientific inquiry rather than in the authority of a religious or moral creed – come to “enact” their own subjugation.[1]
For this vision to make sense, of course, some sense would have to be made of what it means for individuals to be free from self-imposed subjugation and to flourish as a result. Foucault stumbled here because of his insistence that any account of human nature could be used as a means of oppression. It seemed to follow for him that any attempt whatsoever to learn about and regulate human behavior constituted “oppression,” even in cases where the aim was to preserve and enhance human agency or to protect vulnerable members of society from harm.
Thus in The History of Sexuality vol. 1 (p. 31) Foucault characterizes child abuse as nothing more sinister than indulgence in “inconsequential bucolic pleasures,” and suggests that the parents who reported an abuser in a 19th century French village, and the authorities who sought to discipline him, were making a mountain out of a mole hill.
By the time he wrote this, in 1976, Foucault had clearly lost his moral compass.
But this doesn't mean that he wasn’t on to something when he identified forms of influence, some of which can at times have important political implications, that traditional liberal democratic political philosophy finds it difficult to capture. Beyond presenting us with the problem, however, he had no very clear or useful ideas about how to deal with it. His focus was different: Foucault liked to identify what appeared to be small weaknesses in the grand narrative of modernity, and by gnawing at them, so to speak, bring down the whole edifice. He was a fox.
Footnotes
