Joseph Lister & Ivan Povlav

Joseph Lister, 1st Baron Lister, Bt., OM, FRS, PC, known as Sir Joseph Lister, Bt., between 1883 and 1897, was a British surgeon and a pioneer of antiseptic surgery.

Ivan Petrovich Pavlov was a Russian physiologist known primarily for his work in classical conditioning. From his childhood days Pavlov demonstrated intellectual brilliance along with an unusual energy which he named "the instinct for research".