```-	(i) the class of morphisms has to be closed under composition: where f:C1->C2 and g:C2->C3, g o f is also a morphism of the category, which maps C1->C3.
+	(i) the class of morphisms has to be closed under composition: where f:C1→C2 and g:C2→C3, g o f is also a morphism of the category, which maps C1→C3.
(ii) composition of morphisms has to be associative
-	(iii) every element E of the category has to have an identity morphism 1E, which is such that for every morphism f:C1->C2: 1C2 o f = f = f o 1C1
+	(iii) every element E of the category has to have an identity morphism 1E, which is such that for every morphism f:C1→C2: 1C2 o f = f = f o 1C1
```
These parallel the constraints for monoids. Note that there can be multiple distinct morphisms between an element `E` and itself; they need not all be identity morphisms. Indeed from (iii) it follows that each element can have only a single identity morphism. @@ -75,7 +75,7 @@ A **functor** is a "homomorphism", that is, a structure-preserving mapping, betw
``` 	(i) associate with every element C1 of C an element F(C1) of D
-	(ii) associate with every morphism f:C1->C2 of C a morphism F(f):F(C1)->F(C2) of D
+	(ii) associate with every morphism f:C1→C2 of C a morphism F(f):F(C1)→F(C2) of D
(iii) "preserve identity", that is, for every element C1 of C: F of C1's identity morphism in C must be the identity morphism of F(C1) in D: F(1C1) = 1F(C1).
(iv) "distribute over composition", that is for any morphisms f and g in C: F(g o f) = F(g) o F(f)
```