Alexander Fleming

It is a commonplace that the more we know, the more we realize how much there is to know.

The penicillin mold is a very common mold. It grows on bread, on cheese, on old shoes.

The story of penicillin has a certain dramatic interest, but it is not a story of a great scientific discovery, but rather of a lucky accident.

It is not the discovery of a new substance, but the application of an old one, that is important.

The future of chemotherapy lies in the discovery of new substances, not in the modification of old ones.

Many a time I have been asked, 'What is the secret of your success?' My answer is, 'I have no secret.'

The only thing that matters is the patient.

The bacteriologist is a detective, and the bacteria are the criminals.

I am not a hero. I just happened to be there when the mold grew.

It is a strange thing that the things that are most useful are often the most simple.

I have no doubt that the discovery of penicillin will lead to the discovery of many other similar substances.

The world is full of wonders, and we are only just beginning to explore them.

The greatest satisfaction in life is to be able to do something useful for humanity.

The laboratory is a place where one can make mistakes without being punished.

It is not enough to discover; one must also apply.

The doctor of the future will give no medicine, but will interest his patients in the care of the human frame, in diet, and in the cause and prevention of disease.

The mold was a lucky accident, but the observation was not.

I have often been asked what I consider to be the greatest discovery of all time. My answer is always the same: fire.

The man who discovers a new scientific truth has not only the satisfaction of his discovery, but also the joy of seeing it applied to the benefit of mankind.

The history of science is full of examples of discoveries that were made by accident.