“When one door closes another door opens; but we so often look so long and so regretfully upon the closed door, that we do not see the ones which open for us.”

“Concentrate all your thoughts upon the work in hand. The Sun's rays do not burn until brought to a focus”

“Man is the result of slow growth; that is why he occupies the position he does in animal life. What does a pup amount to that has gained its growth in a few days or weeks, beside a man who only att...”

“Don't keep forever on the public road,going only where others have gone, and following one after the other like a flock of sheep. Leave the beaten track occasionally and dive into the woods. 'Every...”

“Don't keep forever on the public road, going only where others have gone.”

“Concentrate all your thoughts upon the work at hand. The sun's rays do not burn until brought to a focus.”

“Dagny," he said, looking at the city as it moved past their taxi window, "think of the first man who thought of making a steel girder. He knew what he saw, what he thought and what he wanted. He di...”

“Our civilization is not Christian. It does not come from the skies. It is not a result of "inspiration." It is the child of invention, of discovery, of applied knowledge -- that is to say, of scien...”

“The day science begins to study non-physical phenomena, it will make more progress in one decade than in all the previous centuries of its existence.”

“I do not know what I may appear to the world, but to myself I seem to have been only like a boy playing on the sea-shore, and diverting myself in now and then finding a smoother pebble or a prettie...”

“To know the history of science is to recognize the mortality of any claim to universal truth. ”

“The scientist only imposes two things, namely truth and sincerity, imposes them upon himself and upon other scientists.”