P48: Love or Hate—say, of Peter—is destroyed if the Sadness the Hate involves, or the Joy the Love involves, is attached to the idea of another cause, and each is diminished to the extent that we imagine that Peter was not its only cause.

Dem.: This is evident simply from the definitions of Love and Hate—see P13 S. For this Joy is called Love of Peter, or this Sadness, Hatred of Peter, only because Peter is considered to be the cause of the one affect or the other. If this is taken away—either wholly or in part—the affect toward Peter is also diminished, either wholly or in part, q.e.d.