haeccitas

philosophy

Written by

The Information Architects of Encyclopaedia Britannica

Last updated

June 29, 2026

Quick Summary

In philosophy, haecceity (or haecceitas) refers to the quality of being a particular individual or thing, often described as "thisness." It is what makes something uniquely itself and distinct from all other entities. This concept is contrasted with "quiddity," which refers to the "whatness" or essential nature of a thing. Haecceity emphasizes individuality and specificity, highlighting the unique characteristics that define a particular instance of something. The term originates from Medieval Latin, derived from the Latin word for "this".12

Summary created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

2 Britannica Sources

Ask Britannica AI about this topic

Britannica doesn't have a full article on this topic, so we've curated a list of our relevant coverage.

Western philosophy
John Duns Scotus
…“individual difference,” or “thisness” (haecceitas). It is an original development of the earlier medieval realism of universals.
Read More
…“individual difference,” or “thisness” (haecceitas). It is an original development of the earlier medieval realism of universals.
Read More