Page "Western esotericism" Paragraph 9

Due to their relative geographic restrictions they were regarded very much as separate disciplines.

It appears that for the most part the specific teachings were preserved via oral tradition ( though not in all cases, the Nag Hammadi Library for example ) passed from teacher to initiate.

However, even in the ancient climates in which they flourished, the Esoteric Philosophies were still highly elusive.

Manly P. Hall writes: