“The willingness to change one’s mind in the light of new evidence is a sign of rationality not weakness.”

“One of the truest signs of strength is accepting one’s own weaknesses.”

“What should we think of someone who never admits error, never entertains doubt but adheres unflinchingly to the same ideas all his life, regardless of new evidence? Doubt and skepticism are signs of rationality. When we are too certain of our opinions, we run the risk of ignoring any evidence that conflicts with our views. It is doubt that shows we are still thinking, still willing to reexamine hardened beliefs when confronted with new facts and new evidence.”

“It is the sign of a weak mind to be unable to bear wealth.”

“For a scientist, altering your doctrines when the facts change is not a sign of weakness.”

“A 'sign of weakness' for a male celebrity is being found to be unfaithful, or unkind to an employee, or having crashed their car while stoned out of their tiny minds. A 'sign of weakness' for a woman, on the other hand, can be a single, unflattering picture.”