"It is not often that one finds a substance that is both highly bactericidal and non-toxic to animal tissues."

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

"The power of observation is crucial in scientific research."

"I often wonder how many other useful molds have been thrown away by bacteriologists."

"I am just a simple bacteriologist who got lucky."