Alexander Fleming — "The thought that I might have discovered something which would be of value in tr…"

"I had no idea that I had stumbled on to a subject that would prove to be of such immense importance."

"The laboratory worker who is not prepared to meet with occasional failures will never achieve success."

"I am only one of many who have contributed to the development of penicillin."

"The time may come when penicillin can be bought by anyone in the shops. Then there is the danger that the ignorant man may easily underdose himself and by exposing his microbes to non-lethal quantitie…"

"I am sometimes asked what I think of the future of penicillin. I think it has a great future, but it must be used wisely."