"The discovery of penicillin was a series of lucky accidents."

"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."

"My own work was really quite simple. I just observed what was happening."

"I am not a very good speaker, but I hope my work speaks for itself."

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