Latin, 17th century
The property of being a unique and individual thing. From the medieval Latin “haecceitas” – “haec,” feminine of “hic,” meaning “this.”
Haecceity is a philosophical concept attributed to Scottish Catholic priest and university professor John Duns Scotus. He defined it as a non-qualitative property of a substance or thing that is responsible for its individuation and identity, such as a particular person’s unique identity. Interestingly, Scotus is also where the term “dunces” originated from. His opponents equated Duns’ followers, who argued against Renaissance humanism, to dullards incapable of scholarship.
Example: I finally realized my haecceity prevents me from being placed in categories designed by others.