Paragraph 118

In plain words

"Sukadeva and those like him were urdhvaretas, men whose seed never fell. Then there is the man whose seed has fallen before, but who holds it from then on: if one is a dhairyareta in this way for twelve years, a special power is born. A new nerve forms within, called the nerve of medha, of retentive intelligence. When that nerve has formed, one remembers everything; one can know everything.