Ancient Philosophy.

Thales: ὕδως, "moisture," is that being which is constant, always already present-at-hand, and lying at the foundation of everything that is and changes. The first cause is the ὕλη, the "material." Anaximenes: ἀήρ, "breath." Heraclitus: πῦρ, "fire." Empedocles: γῆ, earth; although he grasps all the previously mentioned four elements together. Anaximander: his questioning is further advanced. If beings are conceived to be in constant change, but such that something unchanging lies at their foundation, then this that is unchanging must be infinite-in order for the change to be infinite. The ἀπειρία is the basic principle that lies at the foundation of all beings. In this sense, the ὁμοιομεγῆ, the "elements whose parts are alike," are limitless; σύγκρισις and διάκρισις. These theories seem very primitive. But what is decisive is the principle that is investigated and the progress of the research. In order to find correctly the genuine cause of beings, the basic determinations of beings themselves must be disclosed and grasped in advance.

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