Quote by René Descartes

"I think, therefore I am."

"Divide each difficulty into as many parts as is feasible and necessary to resolve it."

"The greatest minds are capable of the greatest vices as well as of the greatest virtues."

"Doubt is the key to knowledge."

"Never underestimate the power of a good laugh."

"Laughter is the best medicine."

"A good laugh is the best medicine."

"Laughter is contagious and wonderful."