Richard Feynman

"Problem-solving becomes easier when you refuse to accept artificial constraints."

"Real understanding shows itself in your ability to explain something simply."

"The details that most people overlook are often the most revealing."

"If you want to learn something, teach it to someone else."

"The pursuit of truth requires more humility than the pursuit of victory."

"Nature is always smarter than our best theories about her."

"What makes life worth living is the constant discovery of new things."

"Authority without understanding is just prejudice wearing a fancy hat."

"The first principle is that you must not fool yourself, and you are the easiest person to fool."

"What I cannot create, I do not understand."

"The pleasure of finding things out is the greatest pleasure of all."

"You don't have to see the whole staircase, just take the first step."

"Cargo cult science is science that follows all the apparent precepts and forms of scientific investigation, but is missing something essential."

"I would rather have questions that can't be answered than answers that can't be questioned."

"The principle of science is that all knowledge must be uncertain."

"Knowing the name of something doesn't mean you understand it."

"When you get the answer, you must check it by substituting back into the original equation."

"The imagination of nature is far, far greater than the imagination of man."

"I learned very early the difference between knowing the name of something and knowing something."

"If you want to master something, teach it."

"Be curious about the world in which you live."

"It is far better to have a permanent income than to be fascinating."

"The worthwhile problems are the ones you can really solve or help solve."

"Never accept an idea because it is traditional; examine it critically."

"In order to make progress, one must leave the door to the unknown open."

"Mathematics is not just a language, it is a language plus logic."

"I am not upset that you lied to me, I am upset that from now on I cannot believe you."

"To develop working ideas efficiently, I type out the reasons why an idea might not work."

"Trying to teach without exciting the student is hard work."

"The most exciting phrase to hear in science is not 'Eureka!' but 'That's funny...'"