「冪対象」の版間の差分

で次の図式

[[File:ExponentialObject-01.png|center|指数対象の普遍性]]

:<math>\mathrm{Hom}(X\times Y,Z) \cong \mathrm{Hom}(X,Z^Y)</math>

が取れる。射 ''g'' および &lambda;''g'' が、互いに他の「指数随伴」(''exponential adjoints'') と呼ばれることもある<ref name="Goldblatt">{{cite book | title = Topoi : the categorial analysis of logic | last1 = Goldblatt | first1 = Robert | authorlink = Robert Goldblatt | publisher = [[North-Holland Publishing Company|North-Holland]] | edition = Revised | year = 1984 | page = 72 | chapter = Chapter 3: Arrows instead of epsilon | isbn = 978-0-444-86711-7 | series = Studies in Logic and the Foundations of Mathematics #98}}</ref>。