> The use of "were" is correct, but you are correct that generally speaking "I" and "he/she/it" are singular. "If he were a babe" is an example of the subjunctive tense, in which there is speculation about what might have been but which is not. It always (I think) follows the word "if," and the plural "were" is used for all subjects. Here are some examples:
>
> "If I were you, I would...."
> "If wishes were roses, I'd have...."
> "If she were my daughter, I'd...."
>

The subjunctive is used in many more types of constructions. The page at the link goes into a good amount of detail on it.