I had to say that

Josiah Willard Gibbs was the greatest American physicist of the 19th century, perhaps the only world-class American physicist of his time.

He was well-known among his friends and peers not only for his brilliance but also for his extraordinary modesty. They were astounded, therefore, when on one occasion when Gibbs was testifying as an expert witness, and the opposing lawyer asked him what right he had to say such things, he replied "I am the greatest living authority on the matter."

Gibbs's explanation after the fact: "I had to say that; I was on oath".


pdf23ds said...

Perhaps it speaks to my considerable ignorance of physics that I know of no laws or principles or effects named after Gibbs.

John Cowan said...

It must. The Gibbs free energy is the best known; see the Wikipedia article for other examples.