Here are four more unattributed quotes. I can't say where they came from but I think that they are too thought-provoking to waste:
"Not only are their questions in search of an answer, there are questions in search of being asking."
"It is a terrible thing when you have ideas and nobody with whom to share them. It is infinity worse when that is the case and you happen to work at a university."
"It is easy to make worthless activity feel valuable. All one has to do is feel tired at the end of it."
"Like everybody else, I make mistakes. The only difference is that my mistakes are at such a level that most people around me can never spot them."
This final quote is not necessarily as conceited as it sounds. If the author of that comment were, in fact, conceited he would never have uttered it in the first place; he would not have admitted to the fact that he made mistakes. Rather, this quote reflects what should surely be everybody's aim: not to make no mistakes at all but make instead only those mistakes that come when probing the limits of understanding.