- Peirce, Benjamin Peirce - United States mathematician and astronomer remembered for his studies of Uranus and Saturn and Neptune (1809-1880)
--1 is a kind of mathematician; astronomer, uranologist, stargazer
- Peirce, Charles Peirce, Charles Franklin Peirce - United States philosopher and logician; pioneer of pragmatism (1839-1914)
--2 is a kind of philosopher; logician, logistician