Self-awareness early philosophical discussion of self-awareness is that of John Locke. Locke was apparently influenced by René Descartes' statement normally translated 'I think, therefore I am' ("Cogito ergo sum"). In chapter XXVII "On Identity and Diversity" of Locke's "An Essay Concerning Human Understanding" (1689) he conceptualized consciousness as the repeated self-identification of oneself through which moral responsibility could be attributed to the subject—and therefore punishment and guiltiness justified, as critics such as Nietzsche would point out, affirming "...the psychology of conscience is not 'the voice of God in man'; it is the instinct of cruelty ... expressed, for the first time,
Cogito, ergo sum one's belief in their own existence would be secure, for there is no way one could be deceived unless one existed in order to be deceived. But I have convinced myself that there is absolutely nothing in the world, no sky, no earth, no minds, no bodies. Does it now follow that I, too, do not exist? No. If I convinced myself of something [or thought anything at all], then I certainly existed. But there is a deceiver of supreme power and cunning who deliberately and constantly deceives me. In that case, I, too, undoubtedly exist, if he deceives me;