Thomas Henry Huxley

The publication of the Darwin and Wallace papers in 1858, and still more that of the ‘Origin’ in 1859, had the effect upon them of the flash of light, which to a man who has lost himself in a dark night, suddenly reveals a road which, whether it takes him straight home or not, certainly goes his way. That which we werelooking for, and could not find, was a hypothesis respecting the origin of known organic forms, which assumed the operation of no causes but such as could be proved to be actually at work. We wanted, not to pin our faith to that or any other speculation, but to get hold of clear and definite conceptions which could be brought face to face with facts and have their validity tested. The ‘Origin’ provided us with the working hypothesis we sought.
‘On the Reception of the Origin of Species‘. In F. Darwin (ed.), The Life and Letters of Charles Darwin, Including an Autobiographical Chapter (1888), Vol 2, 197.
I’m in way too much danger of quoting Huxley way too often. He’s just so damn quotable. Did he ever say anything stupid, ever?

John Ruskin

“When I tell you that war is the foundation of all the arts, I mean also that it is the foundation of all the high virtues and faculties of men. It is very strange for me to discover this, and very dreadful, but I saw it to be quite an undeniable fact… I found, in brief, that all great nations learned their truth of word and strength of thought in war; that they were nourished in war and wasted in peace; taught by war and deceived by peace; trained by war and betrayed by peace; in a word, that they were born in war and expired in peace.”
John Ruskin, Crown of Wild Olive

Yeah, it’s not really science. But interesting.

Carl Sagan

There is a reward structure in science that is very interesting: Our highest honors go to those who disprove the findings of the most revered among us. So Einstein is revered not just because he made so many fundamental contributions to science, but because he found an imperfection in the fundamental contribution of Isaac Newton.
In ‘Wonder and Skepticism’, Skeptical Enquirer (Jan-Feb 1995), 19, No. 1.
Sagan again. What a genius.

Carl Sagan

No scientist likes to be criticized. … But you don’t reply to critics: “Wait a minute, wait a minute; this is a really good idea. I’m very fond of it. It’s done you no harm. Please don’t attack it.” That’s not the way it goes. The hard but just rule is that if the ideas don’t work, you must throw them away. Don’t waste any neurons on what doesn’t work. Devote those neurons to new ideas that better explain the data. Valid criticism is doing you a favor.
In ‘Wonder and Skepticism‘, Skeptical Enquirer (Jan-Feb 1995), 19, No. 1.
But that’s unbearable…