For I am not so enamoured of my own opinions that I disregard what others may think of them.
It is right that we should stand by and act on our principles; but not right to hold them in obstinate blindness.
In science it often happens that scientists say, 'You know that's a really good argument; my position is mistaken,' and then they actually change their minds.
The universe is wider than our views of it.
Progress is impossible without change, and those who cannot change their minds cannot change anything.
It is the mark of an educated mind to be able to entertain a thought without accepting it.
