Given a category without a certain structure, we would like to construct a new category having that structure, in a universal manner . For a category C , the quotients of span category Span(C) provide us a good setting to construct new categories having the given structure of C. For a topos T , we construct new toposes that enjoy extra structures like booleanness, internal axiom of choice and etc. To do this, we study a kind of relations on span category Span(T) that we call them logical relations. Their quotient construction produce toposes with good properties. This is based on a joint project with M. Golshani.