Wigner, Eugene Paul. 1902-1995. Hungarian-born Amer. physicist (Nobel, 1963):
This is Pi
What is this symbol here?
There is a story about two friends, who were classmates in high school, talking about their jobs.
One of them became a statistician and was working on population trends. He showed a reprint to his former classmate.
The reprint started, as usual, with the Gaussian distribution and the statistician explained to his former classmate the meaning of the symbols for the actual population, for the average population, and so on.
His classmate was a bit incredulous and was not quite sure whether the statistician was pulling his leg.
"How can you know that?" was his query. "And what is this symbol here?" "Oh," said the statistician, "this is pi."
"What is that?"
"The ratio of the circumference of the circle to its diameter."
"Well, now you are pushing your joke too far," said the classmate, "surely the population has nothing to do with the circumference of the circle."
"The Unreasonable Effectiveness of Mathematics in the Natural Sciences”, 1960