Philipp Frank

Philipp Frank (March 20, 1884, Vienna, Austria-Hungary – July 21, 1966, Cambridge, Massachusetts, United States) was a physicist, mathematician and also an influential philosopher during the first half of the 20th century. He was a logical-positivist, and a member of the Vienna Circle. He was influenced by Mach and was one of the Machists criticised by Lenin in Materialism and Empirio-criticism.

He studied physics at the University of Vienna and graduated in 1907 with a thesis in theoretical physics under the supervision of Ludwig Boltzmann. Albert Einstein recommended him as his successor for a professorship at the German Charles-Ferdinand University of Prague, a position which he held from 1912 until 1938.

He then emigrated to the United States, where he became a lecturer of physics and mathematics at Harvard University.

In 1947 he founded the Institute for the Unity of Science as part of the American Academy of Arts and Sciences (AAAS). This arose after Howard Mumford Jones (then president of the AAAS) had issued a call to overcome the fractation of knowledge, which he felt the AAAS well suited to address. The institute held regular meetings atrracting a broad range of participants. Quine regarded these organisation as a "Vienna Circle in exile".

Astronomer Halton Arp described Frank's Philosophy of Science class at Harvard as being his favorite elective.

In lectures given during World War II at Harvard, Frank attributed to Mach himself the following graphic expression of Mach's principle:

"When the subway jerks, it's the fixed stars that throw you down."

In commenting on this formulation of the principle, Frank pointed out that Mach chose the subway for his example because it shows that inertial effects are not shielded (by the mass of the earth): The action of distant masses on the subway-rider's mass is direct and instantaneous. It is apparent why Mach's Principle, stated in this fashion, does not fit with Einstein's conception of the retardation of all distant action.

• Philosophy of Science, Prentice Hall (1957)
• Einstein: His Life and Times, A. A. Knopf (1947); 2nd edition, Da Capo Press (2002)
• Foundations of Physics, University of Chicago Press (1946)

• "Review of Einstein. Sein Leben und seine Zeit by Philipp Frank, publ. Vieweg, 468 pages". Bulletin of the Atomic Scientists. 36 (3): 50. March 1980.