We shall study the modes of self-consciousness such as they have been described by A. Millán-Puelles in his work. This article deals exclusively with human self-consciousness, leaving aside other non-human beings gifted with consciousness, and of course, the Divine Being, which should properly be called Absolute Self-Conscience. Furthermore, the kind of selfconsciousness to be dealt with here is but one of the three ways in which the human ego relates with itself.