Dear all, I am searching for Bill Lawvere's 1989 preprint "Intrinsic boundary in certain mathematical toposes exemplify ‘logical’ operators not passively preserved by substitution". It is not available in the internet, nor at any library indexed by worldcat.org. Is there a chance that someone reading this email has a copy of it? (I have a copy of his 1991 text "Intrinsic co-Heyting boundaries and the Leibniz rule in certain toposes", and I am searching specifically for this 1989 preprint.) With best wishes Ryszard ---------- You're receiving this message because you're a member of the Categories mailing list group from Macquarie University. Leave group: https://outlook.office365.com/owa/categories@mq.edu.au/groupsubscription.ashx?source=EscalatedMessage&action=leave&GuestId=6bf90c14-94d1-45b7-a0b5-9dd447734d27