Dear All, I wish you and your family a Happy Easter :) In a festive spirit of Easter (somewhat dual to Christmas lectures [presumably of answers]), I have an Easter question: Having learned that (i) coproducts are isomorphic to products in linear categories (zero object: 1 = 0; https://lawverearchives.com/wp-content/uploads/2024/12/1992-categories-of-sp..., p. 17), and (ii) pieces = points is the defining condition of quality type (https://lawverearchives.com/wp-content/uploads/2025/01/2007-Axiomatic-cohesi..., p.43), I added a few mundane ones such as the circle resulting from coincidence of the two endpoints of a straight line segment, dynamical systems resulting from codomain = domain, and isomorphisms resulting from a map being being both epi and mono. Given that existence of limits and colimits is of immense significance in category theory, along with attendant arrow reversal in going from a concept to its coconcept (and vice-versa; although reversing the arrows in the definition of product gives the definition of sum, unlike the definition of product that can be used to calculate products, sums can only be verified based on the definition of sum, cf. co-element; Lawvere & Rosebrugh, Sets for Mathematics, pp. 127-128), I'd be grateful to you for any pointers you may have regarding the general significance (conditions for and consequences) of: colimit = limit. Thanking you, Yours respectfully, posina You're receiving this message because you're a member of the Categories mailing list group from Macquarie University. To take part in this conversation, reply all to this message. View group files<https://outlook.office365.com/owa/categories@mq.edu.au/groupsubscription.ashx?source=EscalatedMessage&action=files&GuestId=6bf90c14-94d1-45b7-a0b5-9dd447734d27> | Leave group<https://outlook.office365.com/owa/categories@mq.edu.au/groupsubscription.ashx?source=EscalatedMessage&action=leave&GuestId=6bf90c14-94d1-45b7-a0b5-9dd447734d27> | Learn more about Microsoft 365 Groups<https://aka.ms/o365g>