The teachings of Humanities greatest seers are fundamentally one.
“There is only one absolute Truth. Being Universal, it is seen alike by all who are able to perceive it.” -Franz Hartmann
Truth is One, the sages speak of it by many names
– Rig Veda Samhita 1.164.46
Who sees variety and not the unity wanders on from death to death
– Katha Upanishad
Tat Tvam Asi. Thou Art That
– Chandogya Upanishad 6.8.7