Provides the students with competencies and skills in his chosen field.

This he considered a sign of skill and success in his chosen field.

He was not, and is not, cynical about his chosen field.

No university could have taught him what he taught himself in his chosen field.

And where better to tend to those concerns than in his chosen field?

He considers himself a businessman, the top in his chosen field.

For the time being the world, life itself, could be his chosen field.

"Perhaps because I regard him as an amateur in his chosen field."

We can see there are serious problems: he's a perpetual student who can't seem to settle in his chosen field.

He has been active in his chosen field of profession since 1995.