Rudolf Emil Kalman

“Whenever a model is built, it is always proper to ponder the basic scientific question: is the model really based on the data or is an artifact displaying the prejudices of its creator?” Rudolf Emil Kalman, Kyoto Prize address

Maxwell

An experiment, like every other event which takes place, is a natural phenomenon; but in a scientific experiment the circumstances are so arranged that the relations between a particular set of phenomena may be studied to the best advantage.

James Clerk Maxwell, 1876

Entropy

You should call it entropy, for two reasons. In the first place your uncertainty function has been used in statistical mechanics under that name, so it already has a name. In the second place, and more important, no one really knows what entropy really is, so in a debate you will always have the advantage.

Suggesting to Claude Shannon a name for his new uncertainty function, as quoted in Scientific American Vol. 225 No. 3, (1971), p. 180.

Qian Xuesen

“An engineering science aims to organize the design principles used in engineering practice into a discipline and thus to exhibit the similarities between different areas of engineering practice and to emphasize the power of fundamental concepts. In short, an engineering science is predominated by theoretical analysis and very often uses the tool of advanced mathematics.”

Qian Xuesen (in English Hsue-Shen Tsien or H.S. Tsien)

Qian Xuesen

“I do not plan to come back. I have no reason to come back. I plan to do my best to help the Chinese people build up the nation to where they can live with dignity and happiness.”

Qian (1955) to reporters after returning to China.

Cited in: “Qian Xuesen dies at 98; rocket scientist helped establish Jet Propulsion Laboratory” Obituary Nov 1, 2009

John von Neumann

“If you say why not bomb them tomorrow, I say why not today? If you say today at five o’ clock, I say why not one o’ clock?”

John von Neumann

As quoted in “The Passing of a Great Mind” by Clay Blair, Jr., in LIFE Magazine (25 February 1957), p. 96

Theodore von Karman

Introduction to Compressible Flow

“We call the speed range just below and just above the sonic speed – Mach number nearly equal to one – the transonic range. Hugh Dryden and I invented the word transonic. We had found that a word was needed to denote the critical speed range of which we were talking. We could not agree whether it should be written with one s or two. Dryden was logical and wanted two s’s. I thought it wasn’t necessary and always to be logical in aeronautics, so I wrote it with one s. I introduced the term in this form in a report to the Air Force. I am not sure whether the general who read it knew what it meant, but his answer contained the word, so it seemed to be officially accepted. I well remember this period (1941) when designers were rather frantic because of the unexpected difficulties of transonic flight. They thought the troubles indicated a failure in aerodynamic theory.” Theodore von Karman at Cornell in lecture, 1953.