"At the opposite extreme to varieties determined by their finite members are those which have only one finite member, the trivial groupoid."
"Categorically any setoid is a trivial groupoid, ie a category where every morphism is an isomorphism."
- Sherman K Stein (April 1963). "Finite models of identities". Proceedings of the American Mathematical Society 14 (02): 216-22. http://www.ams.org/proc/1963-014-02/S0002-9939-1963-0144995-X/S0002-9939-1963-0144995-X.pdf. Retrieved 2015-06-29.
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