“No, this trick won't work. . . . How on earth are you ever going to explain in terms of chemistry and physics so important a biological phenomenon as first love?”

“In the middle of every difficulty lies opportunity.”

“Once you eliminate the impossible, whatever remains, no matter how improbable, must be the truth.”

“It is a capital mistake to theorize before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts.”

“Adapt or perish, now as ever, is nature's inexorable imperative.”