Starting with "I think," Descartes fixed his attention only on the "think," completely neglecting the "I." Now, this I is essential. For Man, and consequently the Philosopher, is not only Consciousness, but also—and above all—Self-Consciousness. Man is not only a being that thinks—i.e., reveals Being by Logos, by Speech formed of words that have a meaning. He reveals in addition—also by Speech—the being that reveals Being, the being that he himself is, the revealing being that he opposes to the revealed being by giving it the name Ich or Selbst, I or Self.
source
Alexandre Kojève, Introduction to the Reading of Hegel: Lectures on the Phenomenology of Spirit, assembled by Raymond Queneau, edited by Allan Bloom, translated by James H. Nichols, Jr. (1969), p. 36