Beyond Good and Evil ( Classics Series) by Friedrich Wilhelm Nietzsche

In the opening two parts of the book, Nietzsche discusses in turn the philosophers of the past, whom he accuses of a blind dogmatism plagued by moral prejudice masquerading as a search for objective truth; and the "free spirits", like himself, who are to replace them.

He casts doubt on the project of past philosophy by asking why we should want the "truth" rather than recognizing untruth "as a condition of life." He offers an entirely psychological explanation of every past philosophy: each has been an "involuntary and unconscious memoir" on the part of its author (§6) and exists to justify his moral prejudices, which he solemnly baptizes as "truths"