The above graphic  of the Pythagorean Y was created by Geoffroy Tory born in Bourges around 1480 and died in Paris before 14 October 1533. He was a French humanist and an engraver, best known for adding accents on letters in French. His life’s work has heavily influenced French publishing to this day.

The Pythagorean Y represents the proverbial fork in the road, where the one fork is towards Virtue and one fork is towards Vice.  Above you will see that the “right” path is to Virtue, and the left  (vice) path leads to falling down into the flames (of hell?)  Both verses below say rocks, but it looks like flames to me.

From Gnostic Warrior:
Pythagoras his forked letter does
Of human life a scheme to us propose
For virtue’s path on the right hand doth lye
An hard ascent presenting to the eye;
But on the top with rest the wearied are
Refreshed; the broad way easier doth appear;
But from its summit the deluded fall;
And dashed among the rocks, find there a funerall

A similar verse, attributed to Virgil:
The right hand track to sacred Virtue tends,
Though steep and rough at first, in rest it ends;
The other broad and smooth, but from its Crown
On rocks the Traveller is tumbled down.
He who to Virtue by harsh toils aspires,
Subduing pains, worth and renown acquires;
But who seeks slothful luxury, and flies,
The labor of great acts, dishonored dies.

Y is called Upsilon, or Ypsilon and is derived from the Phoenecian waw letter.

Phoenecian Alphabet

Pythagoras

From The Basics of Philosophy

Pythagoras of Samos (c. 570 – 490 B.C.) was an early Greek Pre-Socratic philosopher and mathematician from the Greek island of Samos.

He was the founder of the influential philosophical and religious movement or cult called Pythagoreanism and allegedly exercised an important influence on the work of Plato.

Little is known for sure about him, (none of his original writings have survived, and his followers usually published their own works in his name) and he remains something of a mysterious figure. His secret society had a great effect on later esoteric traditions such as Rosicrucianism and Freemasonry.

According to some reports, as a young man he met Thales, who was impressed with his abilities and advised him to head to Memphis in Egypt and study mathematics and astronomy with the priests there, which he soon had the opportunity of. He also traveled to study at the temples of Tyre and Byblos in Phoenicia, as well as in Babylon. At some point he was also a student of Pherecydes of Syros and of Anaximander (who himself had been a student of Thales).

In Croton, Pythagoras established a secret religious society very similar to (and possibly influenced by) the earlier Orphic cult, in an attempt to reform the cultural life of Croton. He formed an elite circle of followers around himself, called Pythagoreans or the Mathematikoi (“learners”), subject to very strict rules of conduct, owning no personal possessions and assuming a largely vegetarian diet. They followed a structured life of religious teaching, common meals, exercise, music, poetry recitations, reading and philosophical study (very similar to later monastic life). The school (unusually for the time) was open to both male and female students uniformly (women were held to be different from men, but not necessarily inferior). The Mathematikoi extended and developed the more mathematical and scientific work Pythagoras began.

Other students, who lived in neighboring areas, were also permitted to attend some of Pythagoras’ lectures, although they were not taught the inner secrets of the cult. They were known as the Akousmatikoi (“listeners”), and they focused on the more religious and ritualistic aspects of Pythagoras’ teachings (and were permitted to eat meat and own personal belongings).

The Enigma of Pythagorus