A blank spot in literary history has described almost nothing about the Pythagoreans. We can weigh the survival options of intelligent people when tyrannized by local savages. After the fatal attack a threatened school might logically wait millennia until future humans were receptive of their hidden teachings. Secrecy was a necessary survival technique preserving dedicated human beings who were esotericians or were seekers to quietly survive unlawfull persecutions, and so Pythagoreans avoided establishing official or any literary contacts and left no clarifying records. (For more, scroll to 1.7 Pythagoras , same link as below).
From Pythagorean’s publications we are informed:
“The esoteric world view and life view has been publicized, so that anyone can gain much knowledge of the matter and consciousness aspects that was formerly strictly secret (even to initiates of lower degrees). Link
“Laurency has taken pains to clear away all symbolism.... as far as possible, to start from the concepts and terms of natural science.
“Nowadays they boast of culture and think they have reached far above barbarism. That is a great illusion, however.
Short Samples from essay:
ESOTERIC KNOWLEDGE ORDERS by Henry T. Laurency
Link : https://www.laurency.com/L3e/L3e1.pdf.
Takeaways: Pythagoras' small colony was destroyed thousands of years ago, and the modern vicinity is viewed by arial photo, to generally see the landscape around Laurency's reference, "outside the town of Taormina in Sicily". The main body of Pythagorean work was successfully kept secret which explains the blank spot in history. A practice without egoism, prominence or power secretly trained selected individuals, without open, cultural intercourse, leaving no records whatsoever.