Among the ethical principles which Pythagoras taught was that men ought
not to pray for anything in particular, since they do not know what is
good for them; that drunkenness was identical with ruin; that no one
should exceed the proper quantity of meat and drink; that the property
of friends is common; that men should never say or do anything in anger.
He forbade his disciples to offer victims to the gods, ordering them to
worship only at those altars which were unstained with blood.

Pythagoras was the first person who introduced measures and weights
among the Greeks. But it is his philosophy which chiefly claims our
attention. His main principle was that _number_ is the essence of
things,--probably meaning by number order and harmony and conformity to
law. The order of the universe, he taught, is only a harmonical
development of the first principle of all things to virtue and wisdom.
He attached much value to music, as an art which has great influence on
the affections; hence his doctrine of the music of the spheres. Assuming
that number is the essence of the world, he deduced the idea that the
world is regulated by numerical proportions, or by a system of laws
which are regular and harmonious in their operations. Hence the
necessity for an intelligent creator of the universe. The Infinite of
Anaximander became the One of Pythagoras. He believed that the soul is
incorporeal, and is put into the body subject to numerical and
harmonical relation, and thus to divine regulation. Hence the tendency
of his speculations was to raise the soul to the contemplation of law
and order,--of a supreme Intelligence reigning in justice and truth.
Justice and truth became thus paramount virtues, to be practised and
sought as the end of life. "It is impossible not to see in these lofty
speculations the effect of the Greek mind, according to its own genius,
seeking after God, if haply it might find Him."