William John Macquorn Rankine

“A hypothetical theory is necessary, as a preliminary step, to reduce the expression of the phenomena to simplicity and order before it is possible to make any progress in framing an abstractive theory,”

William John Macquorn Rankine

Outlines of the Science of Energetics, in Proceedings of the Philosophical Society of Glasgow (1855)

William John Macquorn Rankine

“Discrepancy between theory and practice, which in sound physical and mechanical science is a delusion, has a real existence in the minds of men; and that fallacy, through rejected by their judgments, continues to exert and influence over their acts,”

William John Macquorn Rankine

Introductory Lecture on the Harmony of Theory and Practice in Mechanics (1856), p. 4

Richard Feynman

“Science is the belief in the ignorance of experts,”

Richard Feynman
“What is Science” presented at the fifteenth annual meeting of the National Science Teachers Association, in New York City (1966), published in The Physics Teacher, volume 7, issue 6 (1969), p. 313-320

Wernher von Braun

“The rocket worked perfectly, except for landing on the wrong planet.”

Wernher von Braun (comment on V2 landing on London 1944, Apollo in Perspective : Spaceflight Then and Now (1999))

John Strutt, 3rd Baron Rayleigh

“Without encroaching upon grounds appertaining to the theologian and the philosopher, the domain of natural sciences is surely broad enough to satisfy the wildest ambition of its devotees. The work may be hard, and the discipline severe; but the interest never fails, and great is the privilege of achievement.,”

John Strutt, 3rd Baron Rayleigh

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.

Ernst Mach

“I know of nothing more terrible than the poor creatures who have learned too much. Instead of the sound powerful judgement which would probably have grown up if they had learned nothing, their thoughts creep timidly and hypnotically after words, principles and formulae, constantly by the same paths. What they have acquired is a spider’s web of thoughts too weak to furnish sure supports, but complicated enough to provide confusion.”

Ernst Mach

Leonardo da Vinci

“The object that strikes the air develops a force equal to that of the air that strikes the object. Observe how the beating of its wings against the air suffices to bear up the weight of the eagle in the highest and thinnest air. Observe too that, conversely, the air fills the sails and pushes the heavily laden ship. From this you can understand that man, with great wings, acting against the resistance of air, might overcome it victoriously and rise above it,”

Leonardo da Vinci