“The trouble I have with astrophysics or quantum mechanics is the same problem I have with philosophy; which is: initially it is mind blowing, then it is fascinating, then it is disturbing, then it is almost uncomprehensible, then it's fascinating again, then you disappear up your own ass.”

Preface
Philosophy and the Mirror of Nature (1979)

Letter (9 July 1950); published in Ernest Hemingway: Selected Letters 1917–1961 (1981) edited by Carlos Baker

Does Some Deeper Level of Physics Underlie Quantum Mechanics? An Interview with Nobelist Gerard 't Hooft http://blogs.scientificamerican.com/critical-opalescence/2013/10/07/does-some-deeper-level-of-physics-underlie-quantum-mechanics-an-interview-with-nobelist-gerard-t-hooft/

"A Universe From Nothing" by Lawrence Krauss, AAI 2009 http://www.youtube.com/watch?v=7ImvlS8PLIo

Source: Lectures on Quantum Mechanics (2012, 2nd ed. 2015), Ch. 3: General Principles of Quantum Mechanics

Quoted in Noël Barber, Pierre Jeannerat de Beerski, "Conversations with Painters" (1964), p. 45

Venkatraman Ramakrishnan interview: 'It takes courage to tackle very hard problems in science

Source: Terre des Hommes (1939), Ch. I : The Craft
Context: I had a vision of the face of destiny.
Old bureaucrat, my comrade, it is not you who are to blame. No one ever helped you to escape. You, like a termite, built your peace by blocking up with cement every chink and cranny through which the light might pierce. You rolled yourself up into a ball in your genteel security, in routine, in the stifling conventions of provincial life, raising a modest rampart against the winds and the tides and the stars. You have chosen not to be perturbed by great problems, having trouble enough to forget your own fate as man. You are not the dweller upon an errant planet and do not ask yourself questions to which there are no answers. You are a petty bourgeois of Toulouse. Nobody grasped you by the shoulder while there was still time. Now the clay of which you were shaped has dried and hardened, and naught in you will ever awaken the sleeping musician, the poet, the astronomer that possibly inhabited you in the beginning.
The squall has ceased to be a cause of my complaint. The magic of the craft has opened for me a world in which I shall confront, within two hours, the black dragons and the crowned crests of a coma of blue lightnings, and when night has fallen I, delivered, shall read my course in the stars.

"Testing Quantum Mechanics" http://www.sciencedirect.com/science/article/pii/0003491689902765, Annals of Physics (1989)