Today is the 14th of March, alternatively March 14 or even 3/14. Not unnaturally, today is also Pi Day. Celebrated by mathematicians all over the world in honor of the number Pi (or π), the ratio of a circle’s circumference to its diameter, Pi Day was born at the San Francisco Exploratorium in 1988. Just like the number itself, the ways to celebrate Pi are endless: special events at the Exploratorium, writing piems (poems following the successive numerals of Pi) baking and savoring pies, etc.
By a curious coincidence, March 14 is also Albert Einstein’s birthday and the day, in 1951, when United Press International photographer Arthur Sasse took the famous picture of Einstein sticking out his tongue. Consequently, Pi Day celebrations also include paying homage to the Nobel Prize physicist. Various portraits of Albert Einstein are part of the Photography Collection at the International Center of Photography, including works by Roman Vishiniac, Hansel Mieth, Ernst Haas, and Lucien Aigner.
Roman Vishniac, Albert Einstein, 1951
©Mara Vishniac Kohn, courtesy International Center of Photography
Hansel Mieth, Albert Einstein playing the violin for orphan children in Princeton, New Jersey, 1941
Ernst Haas, Albert Einstein, 1952
Lucien Aigner, Einstein Facing the Universe, 1940
This photograph was taken during a one-day visit by Lucien Aigner at Albert Einstein’s home in Princeton in 1940.
Einstein considered being photographed an intrusion into his privacy. However, Aigner did not ask him to pose and tried to be forgotten by the physicist and his assistants in order to capture the essence of the genius. The result is a series of photographs revealing naturally Albert Einstein’s personality and way to work both at home and at the Institute for Advanced Study.
Einstein himself referred to this image as his favorite of himself. He even wrote a note for Lucien Aigner in German on the mount of the print. Here’s the English translation:
“With the science you are busy
Losing your pants is so easy
The picture however is very pretty
With kind regards
Yours truly
A. Einstein”




