“It is because the method of physics does not satisfy the comprehension that we have to go on further.”

'Why I Am a Suffragist? essay, dated May 14, 1915. Cornerstones of Georgia History, p. 165 http://books.google.com/books?id=0qdkKS2F42MC&pg=PA165&lpg=PA165&dq=rebecca+latimer+felton+why+i+am+a+suffragist&source=bl&ots=B1fM_lWjgv&sig=bOmSGdPp921qKNy3TlmDU3uWaEc#v=onepage&q=rebecca%20latimer%20felton%20why%20i%20am%20a%20suffragist&f=false.

The Stark Munro Letters (1894)
Context: The more we progress the more we tend to progress. We advance not in arithmetical but in geometrical progression. We draw compound interest on the whole capital of knowledge and virtue which has been accumulated since the dawning of time. Some eighty thousand years are supposed to have existed between paleolithic and neolithic man. Yet in all that time he only learned to grind his flint stones instead of chipping them. But within our father's lives what changes have there not been? The railway and the telegraph, chloroform and applied electricity. Ten years now go further than a thousand then, not so much on account of our finer intellects as because the light we have shows us the way to more. Primeval man stumbled along with peering eyes, and slow, uncertain footsteps. Now we walk briskly towards our unknown goal.

Sir Charles to Mrs. Coulter in Ch. 9 : Theft
His Dark Materials, The Subtle Knife (1997)

An Outline of Philosophy Ch.15 The Nature of our Knowledge of Physics (1927)
1920s
Context: Physics is mathematical not because we know so much about the physical world, but because we know so little: it is only its mathematical properties that we can discover.

An Outline of Philosophy Ch.15 The Nature of our Knowledge of Physics (1927)
1920s

Source: Foundation and Empire

Introduction, Beast and Man: The Roots of Human Nature (1979).
Context: Other areas were being mapped by anthropologists, who seemed to have some interest in my problem, but who were inclined (at that time) to say that what human beings had in common was not in the end very important; that the key to all the mysteries did lie in culture. This seemed to me shallow. It is because our culture is changing so fast, because it does not settle on everything that we need to go into these questions.

As quoted by John Ward, The lives of the professors of Gresham college (1740) p. 171. https://books.google.com/books?id=jp5bAAAAQAAJ&pg=PA171
Context: About this time, 1655, having an opportunity of acquainting myself with astronomy by the kindness of Dr. Ward, I apply'd myself to the improving of the pendulum for such observations, and in the year 1656, or 1657, I contriv'd a way to continue the motion of the pendulum, so much commended by Ricciolus in his Almagestum which Dr. Ward had recommended to me to peruse. I made some trials to this end, which I found to succeed to my wish. The success of these made me further think of improving it for finding the longitude; and the method I had made for myself for mechanick inventions, quickly led me to the use of springs, instead of gravity, for the making a body vibrate in any posture. Whereupon I did first in great, and afterwards in smaller modules, satisfy myself of the practicableness of such an invention; and hoping to have made great advantage thereby, I acquainted divers of my freinds, and particularly Mr. Boyle, that I was possessed of such an invention, and crav'd their assistance for improving the use of it to my advantage. Immediately after his majesty's restoration Mr. Boyle was pleased to acquaint the lord Brouncher and Sir with it, who advis'd me to get a patent for the invention, and propounded very probable ways of making considerable advantage by it. To induce them to a belief of my performance, I shewed a pocket watch, accommodated with a spring, apply'd to the arbor of the ballance, to regulate the motion thereof, concealing the way I had for finding the longitude. This was so well approv'd of, that Sir Robert Moray drew me up the form of a patent, the principal part whereof, viz. the description of the watch so regulated, is his own hand writing, which I have yet by me. The discouragement I met with in the management of this affair, made me desist for that time.

Encyclopedia of the Philosophical Sciences (1816)