At what point does the action of doing something become the noun identifying the person?

Take the example of a second-year college student who is taking “Writing Poetry 1.” The person seems to have two linguistic choices to categorize the activity in which she’s engaged when creating a poem. She may say, I write poetry. Or, she may say, I am a poet. Obviously, neither statement excludes the other from being said. One may say both on the same day. My interest, though, is the semantic difference between the two.

Surely, the professor who is teaching that poetry class can say the statement, “I am a poet,” without any sense of falsehood or pretension. The student in that same class, saying that very statement, “I am a poet,” may be queried about such a claim. Have you published your poems yet? How many? Where? How long have you been writing? And so forth, all aimed at someone gaging the veracity of her ownership of the label poet. If she were to say, “I write poems,” the same questions may follow but without the aim of testing the veracity of her statement. The simple fact of writing poems makes the statement I write poems true. What fact, however, makes the statement I am a poet true? What converts the verb to the noun? The activity to the being?

In a recent conversation, someone asked if I considered myself a martial artist. I said yes. But then I got to thinking, do I say, I am a jiu-jitsuka (or jiu-jiteiro or BJJ’er). Sometimes I do. But most of the time in reference to my practice, I say, I train jiu-jitsu. Perhaps this is a result of the unsettled noun by which to call those of us who do jiu-jitsu (three above). Judo has judokas. Easy. Yet, if we take the indeterminancy of which noun to use, at one point can someone call themselves a jiu-jitero. Does it work like the college student? That calling yourself the being of the practice too soon sounds a bit to pretentious, that you haven’t “put enough time” in yet to do so. For me, yes, I am a jiu-jitsuka. I started referring myself as that when I realized I would be doing this for the rest of my life. In terms of rank, this occurred sometime after receiving my purple belt, five or six years into my training (currently I’m closing in at 8 years).

Folks who write have a hard time with this. Are you a poet or someone who writes poetry? Are you a writer or do you write?

When did you become the noun? A jiu-jiteiro? A mechanic? An artist? A gardener? Or even for that matter, a resident of a city, “a New Yorker,” versus “I live in New York.” They say that to become a member of the Conch Republic, a Conch, you need to have lived in Key West, Florida about seven years. Is that the time frame for the transition from activity to identity?