Albert Einstein (March 14, 1879–April 18, 1955) endures as “the quintessential modern genius” for his seminal contributions to science, but he was also a great champion of human rights. In fact, despite having taken a backseat to his scientific legacy, Einstein’s strong humanistic and political convictions are no less notable and revolutionary amid the assumptions of his era. Nowhere do they shine more brilliantly than in his lesser-known exchanges with people of radically different backgrounds and beliefs, always deeply thoughtful, irrepressibly respectful, and driven by an earnest desire for mutual understanding and encouragement — including his conversation with the Indian philosopher Tagore about science and spirituality, his correspondence with Freud about violence, peace, and human nature, and his letter to a little girl in South Africa on why her gender shouldn’t hold her back from pursuing science.

Some might assume that Einstein’s compassionate outlook and unflinching commitment to equality were shaped by his own experience of being on the receiving end of history’s deadliest anti-Semitism. When Hitler took over Germany on January 30, 1933 — twelve years after Einstein earned the Nobel Prize, which had already exposed him to anti-Semitism — he had just left Berlin with his wife Elsa to spend their third winter at CalTech, where Einstein had been invited as visiting faculty. The trip may well have saved his life — mere months later, the situation in Germany became inhumane, then gruesomely lethal, for Jews.

Finding himself a reluctant refugee, Einstein — whom the great author and physicist C.P. Snow declared “Hitler’s greatest public enemy” — proclaimed in the press:

As long as I have any choice in the matter, I shall live only in a country where civil liberty, tolerance and equality of all citizens before the law prevail.

But Einstein’s stance was deeper than the particularities of his own experience and predated that. In 1930, the legendary American author, sociologist, historian, and civil rights icon W.E.B. Du Bois reached out to Einstein for a contribution to The Crisis, the official journal of the National Association for the Advancement of Colored People. Du Bois had co-founded NAACP in 1909, two decades after becoming the first African-American to receive a doctorate from Harvard, where he had studied under and been greatly influenced by the pioneering philosopher and psychologist William James.

Dr. Du Bois’s correspondence with Einstein, included in Einstein on Race and Racism (public library), begins with this magnificently courteous invitation from October 14, 1931 — a sublime manifestation of why Virginia Woolf considered letter writing “the humane art,” and a wistful reminder of how different modern life would be if we corresponded with each other in this way — originally written in German and sent while the scientist was still living in Berlin, where Du Bois had studied on a fellowship during his graduate work:

Sir: I am taking the liberty of sending you herewith some copies of THE CRISIS magazine. THE CRISIS is published by American Negroes and in defense of the citizenship rights of 12 million people descended from the former slaves of this country. We have just reached our 21st birthday. I am writing to ask if in the midst of your busy life you could find time to write us a word about the evil of race prejudice in the world. A short statement from you of 500 to 1,000 words on this subject would help us greatly in our continuing fight for freedom. With regard to myself, you will find something about me in “Who’s Who in America.” I was formerly a student of Wagner and Schmoller in the University of Berlin. I should greatly appreciate word from you. Very sincerely yours, W. E. B. Du Bois

Two weeks later, 51-year-old Einstein replied, with equal courtesy, in the affirmative:

My Dear Sir! Please find enclosed a short contribution for your newspaper. Because of my excessive workload I could not send a longer explanation. With Distinguished respect, Albert Einstein

Du Bois translated Einstein’s essay himself and introduced it in The Crisis with the following laudatory “Note from the Editor”:

The author, Albert Einstein, is a Jew of German nationality. He was born in Wurttemburg in 1879 and educated in Switzerland. He has been Professor of Physics at Zurich and Prague and is at present director of the Kaiser-Wilhelm Physical Institute at Berlin. He is a member of the Royal Prussian Academy of Science and of the British Royal Society. He received the Nobel Prize in 1921 and the Copley Medal in 1925. Einstein is a genius in higher physics and ranks with Copernicus, Newton and Kepler. His famous theory of Relativity, advanced first in 1905, is revolutionizing our explanation of physical phenomenon and our conception of Motion, Time and Space. But Professor Einstein is not a mere mathematical mind. He is a living being, sympathetic with all human advance. He is a brilliant advocate of disarmament and world Peace and he hates race prejudice because as a Jew he knows what it is. At our request, he has sent this word to THE CRISIS with “Ausgezeichneter Hochachtung” (“Distinguished respect”).

Although titled “To the American Negro” — a phrase confined to both specific geography and, by virtue of its dated language, a bygone era — Einstein’s short essay bears enduring resonance for all varieties of oppression, discrimination, and the woeful pathology of in-group/out-group polarization to which humanity is so easily susceptible. (Another duo of humanists, Tolstoy and Gandhi, explored that lamentable tendency of ours in their own little-known correspondence.) In a sentiment that calls to mind Kierkegaard’s poignant 19th-century remarks about minority-majority dynamics, Einstein writes:

It seems to be a universal fact that minorities, especially when their Individuals are recognizable because of physical differences, are treated by majorities among whom they live as an inferior class. The tragic part of such a fate, however, lies not only in the automatically realized disadvantage suffered by these minorities in economic and social relations, but also in the fact that those who meet such treatment themselves for the most part acquiesce in the prejudiced estimate because of the suggestive influence of the majority, and come to regard people like themselves as inferior. This second and more important aspect of the evil can be met through closer union and conscious educational enlightenment among the minority, and so emancipation of the soul of the minority can be attained. The determined effort of the American Negroes in this direction deserves every recognition and assistance. Albert Einstein

Einstein on Race and Racism goes on to undo the “historical amnesia” about the iconic scientist’s passionate commitment on antiracism, both public and private, including the forgotten history of his friendship with the African-American singer, actor, and civil rights activist Paul Robeson. Complement it with Margaret Mead, writing thirty years later, on the root of racism and how to counter it, then revisit Einstein on the fickleness of fame, the secret of learning anything, and why we’re alive.