Q. I cannot find a reference to this in my Manual: because versus since. I have been tutored that because is used for instances of cause/effect and that since is for time. However, one of my authors is a scholar who contends that “since denotes a state of being based on a relationship. . . . Because implies causality between one aspect of that relationship and the other.” Can you explain this to me more clearly or refute it altogether?
A. All you need is a dictionary—you and your author seem to be following variations on an old superstition. CMOS covers this in the “Word Usage” section under the word since: “This word may relate either to time {since last winter} or to causation {since I’m a golfer, I know what ‘double bogey’ means}. Some writers erroneously believe that the word relates exclusively to time. But the causal since was a part of the English language before Chaucer wrote in the fourteenth century, and it is useful as a slightly milder way of expressing causation than because. But where there is any possibility of confusion with the temporal sense, use because.”