In From Kant to Husserl, Charles Parsons examines a wide range of historical opinion on philosophical questions, from mathematics to phenomenology. Amplifying his early ideas on Kant’s philosophy of arithmetic, Parsons uses Kant’s lectures on metaphysics to explore how his arithmetical concepts relate to the categories. He then turns to early reactions by two immediate successors of Kant, Johann Schultz and Bernard Bolzano, to shed light on disputed questions regarding interpretation of Kant’s philosophy of mathematics. Interested, as well, in what Kant meant by “pure natural science,” Parsons considers the relationship between the first Critique and the Metaphysical Foundations of Natural Science. His commentary on Kant’s Transcendental Aesthetic departs from mathematics to engage the vexed question of what it tells about the meaning of Kant’s transcendental idealism.

Proceeding on to phenomenology, Parsons examines Frege’s evolving idea of extensions, his attitude toward set theory, and his correspondence, particularly exchanges with Russell and Husserl. An essay on Brentano brings out, in the case of judgment, an alternative to the now standard Fregean view of negation, and, on truth, alternatives to the traditional correspondence view that are still discussed today. Ending with the question of why Husserl did not take the “linguistic turn,” a final essay included here marks the only article-length discussion of Husserl Parsons has ever written, despite a long-standing engagement with this philosopher.

In this illuminating collection, Charles Parsons surveys the contributions of philosophers and mathematicians who shaped the philosophy of mathematics over the course of the past century.

Parsons begins with a discussion of the Kantian legacy in the work of L. E. J. Brouwer, David Hilbert, and Paul Bernays, shedding light on how Bernays revised his philosophy after his collaboration with Hilbert. He considers Hermann Weyl’s idea of a “vicious circle” in the foundations of mathematics, a radical claim that elicited many challenges. Turning to Kurt Gödel, whose incompleteness theorem transformed debate on the foundations of mathematics and brought mathematical logic to maturity, Parsons discusses his essay on Bertrand Russell’s mathematical logic—Gödel’s first mature philosophical statement and an avowal of his Platonistic view.

Philosophy of Mathematics in the Twentieth Century insightfully treats the contributions of figures the author knew personally: W. V. Quine, Hilary Putnam, Hao Wang, and William Tait. Quine’s early work on ontology is explored, as is his nominalistic view of predication and his use of the genetic method of explanation in the late work The Roots of Reference. Parsons attempts to tease out Putnam’s views on existence and ontology, especially in relation to logic and mathematics. Wang’s contributions to subjects ranging from the concept of set, minds, and machines to the interpretation of Gödel are examined, as are Tait’s axiomatic conception of mathematics, his minimalist realism, and his thoughts on historical figures.