Héctor-Neri Castañeda (December 13, 1924 – September 7, 1991[4]) was a Guatemalan-American philosopher and founder of the journal Noûs.
Born in San Vicente, Zacapa, Guatemala, he emigrated to the United States in 1948 and studied under Wilfrid Sellars at the University of Minnesota, where he earned a B.A.
Castañeda received his Ph.D. in June 1954 from the University of Minnesota for his dissertation The Logical Structure of Moral Reasoning.
Castañeda is noted for his development of guise theory, which he applied to outstanding problems in the analysis of thought, language, and the structure of the world.
[3] He referred to these objects collectively as "guises", and argued that they could be treated as sets of properties.
"[14][15] Castañeda introduced the concept of the quasi-indexical (or quasi-indicator), a linguistic device by which one person can attribute an indexical reference to another.