CTJC Bulletin Rosh Hashanah 2020

The finite and the infinite A review of “The beginning of infinity” by David Deutsch, and other thoughts Jonathan Allin This is partly a review of “The beginning of infinity” by David Deutsch, and partly reflections on the finite and infinite prompted by the book.

I’ve attempted to bring together ideas from philosophy, science and cosmology, mathematics, and of course Jewish thinking.

My excuse for including this review is that Deutsch, a theoretical physicist, is Jewish, was born in Haifa, educated in Cambridge and the Other Place, and now works at the Other Place.

A better title for Deutsch’s book would be “The beginning of universality”. Why do some ideas, such as the alphabet, writing, commerce, scientific ideas, become ubiquitous? Unfortunately Deutsch deliberately conflates infinity with “unbounded” and with universality, treating these three separate concepts (to my mind) as a single concept.

Deutsch makes a valid point: a good scientific idea has survived debate and criticism, and will thus over time become universal. Indeed this must be the definition of good science, which nonetheless doesn’t preclude ideas from evolving or being replaced with better ideas that fit more of the available observations. The history of philosophy, on the other hand, is at the mercy of inevitably sketchy, inaccurate, or ambiguous record keeping. We don’t really know what Socrates said, but only what Plato reported that he said. Whereas science has unambiguously moved forward, the same cannot be said of our social or political systems: we continue to suffer decades of misery interspersed with short periods of social enlightenment.

Deutsch states that human progress started with the Enlightenment (from the end of the 17th century to the start of the 19th century, the “long” century), and even then distinguishes between the British Enlightenment and the Continental Enlightenment. The former was Page 42