“If I were to remain silent, I'd be guilty of complicity.”

“As far as I'm concerned, I prefer silent vice to ostentatious virtue.”

“If I could do it all again, I'd be a plumber.”

“I would not think that philosophy and reason themselves will be man's guide in the foreseeable future; however, they will remain the most beautiful sanctuary they have always been for the select few.”

“If I had an hour to solve a problem I'd spend 55 minutes thinking about the problem and 5 minutes thinking about solutions.”

“I'd rather be an optimist and a fool than a pessimist and right.”

“If I were not a Jew I would be a Quaker.”