Alexander Fleming

I certainly did not plan to revolutionise all medicine by discovering the world's first antibiotic, or killer of bacteria. But I suppose that is exactly what I did.

When I woke up just after dawn on September 28, 1928, I certainly didn't plan to revolutionize all medicine by discovering the world's first antibiotic, or bacteria killer. But I suppose that was exactly what I did.

One sometimes finds what one is not looking for.

It is not difficult to make microbes resistant to penicillin in the laboratory by exposing them to concentrations not sufficient to kill them, and the same thing has occasionally happened in the body.

The story of penicillin has a certain romantic appeal, and I think that may be one of the reasons it has attracted so much attention. But the real story is much more prosaic.

Nature makes penicillin; I just found it.

My only merit is that I did not discard the cultures at an early stage.

The thought that I might have discovered something which would be of value in treating disease was, of course, uppermost in my mind.

It is remarkable how easily the public can be misled by sensational statements.

I have been asked by many people how I came to discover penicillin. The answer is that I did not discover it. I just happened to notice it.

The accidental contamination of my cultures by a mold was not an unusual event in a bacteriological laboratory. What was unusual was my decision to investigate the mold.

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

The mere fact that a substance has bactericidal powers does not mean that it can be used for the treatment of septic infections.

It is the common lot of discoverers to be misunderstood.

I was not a great scientist, but I was a careful observer.

The public will probably never understand the difficulties that beset the path of the original investigator.

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

I have been accused of being untidy. I confess to being untidy, but I have never allowed my untidiness to interfere with my work.

The next time you are tempted to throw away a contaminated culture, remember the penicillin.

It is not the discovery of a new substance that is important, but the recognition of its properties.