ABSTRACT
In thanking those who were present April 8, 1929 for the celebration of his seventieth birthday, Edmund Husserl made specific mention of two of his former teachers: Franz Brentano, of course, and, with particular emphasis, Karl Weierstrass, the mathematician credited with placing the infinitesimal calculus upon a rigorous basis. The fact that Husserl started from mathematics, and that he was schooled in the idea of mathematical exactitude, is of decisive importance for his scientific personality, although this in no way requires that phenomenology must actually begin with the mathematical problematic. Husserl was not the only one at the turn of the century to oppose the psychologism current in logic at this time. Husserl carries on the great "idealistic" tradition of Leibniz, Kant, and—despite his personal aversion to romantic philosophy—German Idealism, and not the "psychologistic" philosophy of Berkeley.
