[danaris]

Specialization is for societies.

No human has the capability to learn to do all the things necessary to sustain a modern technological lifestyle solo, with the limited time we have on this planet. At best, someone who's wealthy enough not to have to do all the boring, time-consuming parts might be able to learn a decent subset.

Heinlein's purported philosophy fits very well with the all-too-American "rugged individualist" perspective that every person should be completely self-sufficient, but it doesn't actually hold up if you study psychology, sociology, or history.

It is, perhaps, also relevant that this quote is from the book "Time Enough for Love", whose main character, Lazarus Long, has been alive for many centuries.