In the most recent New York Review of Books, Freeman Dyson reviews Why Does the World Exist?: An Existential Detective Story, by Jim Holt, which is based on interviews with modern philosophers. Freeman titles his review “What Can You Really Know.” Toward the end, he compares philosophy now to what philosophy used to be:

For most of the twenty-five centuries since written history began, philosophers were important. Two groups of philosophers, Confucius and Lao Tse in China, and Socrates, Plato, and Aristotle in Greece, were dominant figures in the cultures of Asia and Europe for two thousand years. Confucius and Aristotle set the style of thinking for Eastern and Western civilizations. They not only spoke to scholars but also to rulers. They had a deep influence in the practical worlds of politics and morality as well as in the intellectual worlds of science and scholarship.

In more recent centuries, philosophers were still leaders of human destiny. Descartes and Montesquieu in France, Spinoza in Holland, Hobbes and Locke in England, Hegel and Nietzsche in Germany, set their stamp on the divergent styles of nations as nationalism became the driving force in the history of Europe. Through all the vicissitudes of history, from classical Greece and China until the end of the nineteenth century, philosophers were giants playing a dominant role in the kingdom of the mind.

Holt’s philosophers belong to the twentieth and twenty-first centuries. Compared with the giants of the past, they are a sorry bunch of dwarfs. They are thinking deep thoughts and giving scholarly lectures to academic audiences, but hardly anybody in the world outside is listening. They are historically insignificant. At some time toward the end of the nineteenth century, philosophers faded from public life. Like the snark in Lewis Carroll’s poem, they suddenly and silently vanished. So far as the general public was concerned, philosophers became invisible.