Sentence:  It follows that for each object "A" its endomorphisms End<sub>"C"</sub>("A") = "C"("A","A") has the structure of what is now called a <WSD>rig</WSD>, that is to say a (commutative) ring without negatives. 
Meaning of the word marked with <WSD> tags:  An algebraic structure similar to a ring, but without the requirement that every element have an additive inverse.