"The greatness of a nation and its moral progress can be judged by the way its animals are treated. I hold that, the more helpless a creature, the more entitled it is to protection by man from the cruelty of human kind" Ghandi
"A dog is not "almost human", and I know of no greater insult to the canine race than to describe it as such." John Holmes
"Facts do not cease to exist because they are ignored." Aldous Huxley
"The chief source of problems are solutions." Eric Sevareid
"The nature of the human species is to reject what is true but
unpleasant and to embrace what is obviously false but
comforting." H.L. Mencken
"By their urge to self-preservation and pursuit of happiness, people are naturally inclined to think in the first place about themself, they are born egoists." Spinoza
"The man who moves a mountain begins by carrying away small stones."
Confucius
"Any society that would give up a little liberty to gain a little security will deserve neither and lose both." Benjamin Franklin
"It is not the strongest of the species that survive, but the one most responsive to change." Charles Darwin
(Used this one only a couple days ago to someone who thought humans were the top of evolution)
Few funny ones:
"People can have the Model T in any color - so long as it's black." Henry Ford
"You can get more of what you want with a kind word and a gun than you can with just a kind word." Al Capone
"Never trust a computer you can't throw out a window." Steve Wozniak
People that play or have played civilization 4 might recognize a few