States of matter
Decay is a concept that preoccupies humanity directly or indirectly since antiquity. Pre-Socratic philosophers approached decay in a cosmological way much like they approached the nature of matter. Empedocles, combining the most prevalent cosmological principles of his time, taught that the Universe can be composed of and decomposed into the four changeless elements of water, earth, wind and fire. With this multi-elemental notion Empedocles explained birth and decay as a “mixing” and “composite” of the four unchangeable elements, which in different proportion and relation to each other make up every physical form. After Plato and the transition to the era of humanism, thinkers started using the concept of decay in reference to the sociopolitical aspect of human development. Aristotle, in his work “On Generation and Corruption” talks about the distinction between governmental powers and the interaction between them, which eventually results in the corruption of a governmental system at the political level as this system becomes similar to another.