"Only the masochist would choose to study Russian" or "Only a masochist would choose to study Russian"? (use of articles in generic noun phrases)

From English is not Normal, by John McWhorter:

If someone were told he had a year to get as good at either Russian or Hebrew as possible, and would lose a fingernail for every mistake he made during a three-minute test of his competence, only the masochist would choose Russian – unless he already happened to speak a language related to it.

Could we substitute "a" for "the" here? Both "the masochist" and "a masochist" are generic noun phrases.

If someone were told he had a year to get as good at either Russian or Hebrew as possible, and would lose a fingernail for every mistake he made during a three-minute test of his competence, only a masochist would choose Russian – unless he already happened to speak a language related to it.

Would this be okay? If not, why?

Answer

I'm another native speaker who can attest that a masochist is fine here.

Since the sentence is not taking about any particular masochist, then I agree with you that it is taking about a generic masochist. So I have to turn to John Lawler's post Re: A question about the generic use of..., which succinctly explains the difference in generic noun phrases when you use a and the. I assume you've read this page, probably several times.

The masochist is the definite generic, which refers to

the Prototype of a species, roughly the image we associate with tiger...

and

a masochist

refers to the Definition of a species, that is, those properties that are absolutely necessary for anything to be a member. It doesn't work as the subject of any predicate that isn't definitional. But with a definitional property, it's certainly true for any member.

Since the sentence would then assert what any masochist would do, then yes, using the indefinite generic is fine here. At least that's how I interpret my intuitive and unflinching assurance that a masochist is fine here.

By the way, I tried to create a tag generic noun phrase but it got shot down without any reason given. Since not even English speakers are taught what they are, I think it's an important and germane topic for this site. Maybe someone should do a metapost about it but I feel like I did my part and really don't want to repeat my attempt.

Edit: okay, thanks for creating the tag.