Thus the inhabitants of Guinea, and of the coast lands especially, have survived by retreating and adapting themselves to conditions in which no others wished to dwell.

The requirements of adaptation were peculiar.

To live where nature supplies Turkish baths without the asking necessitates relaxation.

But since undue physical indolence would unfit people for resistance to parasites and hostile neighbors, the languid would perish.

Relaxation of mind, however, brought no penalties.