Four Modern Philosophers. Carnap, Wittgenstein, Heidegger, Sartre (University of Chicago

Heidegger,

On the Way to Language (Harper and Row, New York, 1971).

Karl Popper, 'The Demarcation Between Science and Metaphysics’, in

The Philosophy of Rudolf Carnap (Open Court, La Salle, 1963).

W. V. O. Quine,

From a Logical

(Harvard University Press, Cambridge, Mass., 1980).

Wilfrid Sellars,

Empiricism and the

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