On November 26, 1857, Swiss linguist and semiotician Ferdinand de Saussure was born. His ideas laid the foundation for many significant developments both in linguistics and semiotics in the 20th century. Moreover, de Saussure is widely considered one of the fathers of 20th-century linguistics and together with Charles Sanders Peirce one of two major fathers of semiotics.
On November 17, 1790, German mathematician and astronomer August Ferdinand Möbius was born. He is best known for his discovery of the Möbius strip, a non-orientable two-dimensional surface with only one side when embedded in three-dimensional Euclidean space