Philosophy - Historical and Collected Persons Treatment - addresses, essays Plato - The Individual as an Object of Love|Aristotle - On Learning to be Good|Aquinas - Intentionality|Hobbes - His Concept of Obligation|Descartes - Cogito and Sum|Spinoza - His Identity Theory|Locke - Primary and Secondary Qualities|Leibniz and Descartes - Proof and Eternal Truths|Berkeley - His Immaterialism and Kant's Trancendental Idealism|Hume - Action, Reason, and Passion|Kant - The Critique of Pure Reason|Hegel - of Faces and Skulls|Mill - The Ends of Life and the Preliminaries of Morality|Marx - The Critique of Justice|Nietzsche - Art and Artists|Frege - Sense and Reference|Russell - The Theory of Descriptions, Names, and Reality|Wittgenstein - His Treatment of the Will|Sartre - Shame, or, The Problem of Other Minds