As against these theories the Eleatics maintained that the true explanation of things lies in the conception of a universal unity of being.
Most famous in connexion with this kind of poetry are Xenophanes and Parmenides, the Eleatics and Empedocles of Agrigentum.
Illingworth has said very concisely: " The physical speculations of the Ionians and Atomists rendered a God superfluous, and the metaphysical and logical reasoning of the Eleatics declared Him to be unknowable."
His arguments were drawn from the dialectic which the Eleatics had directed against the existence of the phenomenal world.
Between Leucippus and Democritus there is an interval of at least forty years; accordingly, while the beginnings of Atomism are closely connected with the doctrines of the Eleatics, the system as developed by Democritus is conditioned by the sophistical views of his time, especially those of Protagoras.