The second essay seeks to explain the origin and history of such ideas as "guilt," and "bad conscience." After relating the ideas to business contracts, Nietzsche hypothesizes that bad conscience is "the serious illness" contracted by man under the stress of becoming a part of a peaceful society, when all his instincts drive him towards "the wilderness, to war, to prowling, to adventure."
The third essay asks, "What is the Meaning of Ascetic Ideals?" Its deepest answer is that the ascetic ideal, though it is anti-life, a will to nothingness, is still an attempt to save the will, in the face of existential absurdity.
Nietzsche as historian:
. . . there is for historiography of any kind no more important proposition than the one it took such effort to establish but which really ought to be established now: the cause of the origin of a thing and its eventual utility, its actual employment and place in a system of purposes, lie worlds apart; whatever exists, having somehow come into being, is again and again reinterpreted to new ends, taken over, transformed, and redirected by some power superior to it; all events in the organic world are a subduing, a becoming master, and all subduing and becoming master involves a fresh interpretation, an adaptation through which any previous "meaning" and "purpose" are necessarily obscured or even obliterated.
(. . . art, in which precisely the lie is sanctified and the will to deception has a good conscience, is much more fundamentally opposed to the ascetic ideal than is science: this was instinctively sensed by Plato, the greatest enemy of art Europe has yet produced. Plato versus Homer: that is the complete, the genuine antagonism--there the sincerest advocate of the "beyond," the great slanderer of life; here the instinctive deifier, the golden nature. To place himself in the service of the ascetic ideal is therefore the most distinctive corruption of an artist that is all possible; unhappily, also one of the most common forms of corruption, for nothing is more easily corrupted than an artist.)