TITLE: Can a vector space have more than one zero vector?
QUESTION [9 upvotes]: The question above is really it. The reason I ask is that my text says a vector space can have more than one zero vector (It's a true/false question: A vector space may have more than one zero vector). But if the zero vector in any space is unique, then it has only one zero vector, no? 
Or am I reading "unique" wrong?

REPLY [4 votes]: Only one. To see it, let $O_1$ and $O_2$ be two zero vectors, then we have $O_2=O_2+O_1=O_1$.