"The world is full of interesting things. You just have to look for them."

"I am often asked if I foresaw the impact of penicillin. My honest answer is no."

"It is a remarkable fact that this substance, which is so potent against bacteria, is almost harmless to animal tissues."

"It is not enough to discover a thing; one must also know how to use it."

"I was not looking for penicillin when I discovered it. I was looking for a better antiseptic."