By Rabbi Richard Baroff

Last year and this year we celebrated the centennial of one of the greatest intellectual achievements in the history of humankind: the publication of Albert Einstein’s general theory of relativity, which is in essence his theory of gravitation.

It is a testament to his greatness as a scientific figure that his conception of gravitation is universally accepted as the explanation of gravity within physics and astronomy. The theory has been verified many times. First published near the end of 1915, it was in 1916 that this new theory was widely discussed and examined by physicists.

One prediction of general relativity that had not been verified until this year was the existence of gravitational waves. This discovery occurred fortuitously in the centenary year of the theory.

General relativity was of course an expansion and continuation of the special theory of the decade before. Taken together, the special and general theories revolutionized humankind’s ideas of time and space and of matter and energy. So far, all of it has been scientifically verified.

The general theory was published in the midst of the Great War, during the dark time of the Battles of the Somme and Verdun. But Einstein was only celebrated by the general public after the war in 1919, when the prediction that a beam of light would bend around the sun was shown to be true.

In the 1920s Einstein and his somewhat older contemporary Sigmund Freud became scientific celebrities. Their revolutionary ideas remain central to science and important in human culture. But they are different. Whereas Einstein’s theories have been verified, Freud’s have not and indeed cannot, at least in the same way.

Both Freud and Einstein were proud to call themselves Jewish. Neither was a practicing Jew. Freud was an atheist. Einstein believed in G-d, but in Spinoza’s G-d: G-d as the structure of cause and effect within the cosmos, making human understanding possible. This pantheistic vision of divinity lies outside the Jewish tradition. (Spinoza himself was excommunicated.)

One other figure of Jewish background who would also have a tremendous effect on world culture and history after World War I was Karl Marx. He also professed to be a scientist — in his case, the relatively new science of economics. Those who believed in him and called themselves Marxist maintained that his theories were also proven to be true empirically — every bit as much as either Einstein’s or Freud’s theories.

Unlike Einstein or Freud, Marx lived his entire life in the 19th century. But his massive and explosive impact on the world occurred in the 20th century. Like Freud and Einstein, Marx did not profess Judaism. Like Freud, Marx was an atheist.

But unlike Einstein and Freud, Marx was not proud of his Jewish heritage (both his grandfathers were rabbis). He had a low opinion of both Jews and Judaism — and in fact all religion.

Most of the 20th century was profoundly influenced by these three seminal thinkers: Einstein the mathematical scientist, Freud the speculative scientist, Marx the pseudoscientist.

All came from Jewish backgrounds. None practiced Judaism directly or believed in the G-d of the Bible or rabbinic literature. Freud and Marx were atheists. Freud and Einstein identified with the Jewish people. Einstein was an active Zionist who was offered the presidency of Israel.

It is worth pointing out that in this century Einstein is largely celebrated by the Jewish people. Our pride regarding Freud’s accomplishments and influence is more ambivalent and complicated. As for Marx, his seismic, and largely negative, effect on world politics has made him by far the most controversial thinker of the three.

That none of the three found Judaism appealing as a religion is an indication of the challenges of the modern age and its rampant secularism. Indeed, the secularism of our day is itself fructified by Einstein’s theories, as well as by Freudian and Marxist ideas.

The centenary of Einstein’s general relativity theory is itself a milestone in intellectual, scientific and Jewish history to be sure. Yet ironically it is one of the milestones of our secular age that have undermined the religion of Judaism itself.

Rabbi Richard Baroff leads Guardians of the Torah.