Fire, Water, Earth, Air Ionian (Milesian) school's four fundamental generative modes of existence, in material terms, expressed in two opposite pairs: Wet vs Dry, Cold vs Hot. In an attempt to explain the world that at least appears to be varied that Parmenides seems to be dismissive of, Empedocles (of the Eleatic school) turns the two pairs into four fundamental ingredients of reality: 1. Fire as rarefied version of hotness 2. Air as rarefied version of coldness 3. Water as rarefied version of wetness 4. Earth as rarefied version of dryness Although these elements serve as the fundamental ingredients of the world of appearances, their interactions are explained through principles of love and strife, which respectively explain attraction, and repulsion.[^1] These elements, just like the Chinese five elements 五行, become foundational for shaping how the Greeks and later the Romans perceive and categorize everything in the world. Medicinal practices of that time are done using this model of elements. This in turn is serves as the root for modern psychology.[^2] [^1]: [[James Orr]], "2. The Eleatic School," *[[PA Ancient Philosophy]]*, [[Peterson Academy]]. [^2]: [[Keith Campbell]], "1. [[Roots of Psychology]]," *[[PA Intro to Psychology]]*, [[Peterson Academy]]. Up: [[Elements]]