Generation and Corruption in Greek Philosophy

The importance of better understanding the Aristotelian view within Greek thought in relation to the present theme (On Generation and Corruption) is due to the current knowledge on Physics that is more “Aristotelian” than last century’s, when the value of Democritus was exaggerated. The metaphysical view of Parmenides was mainly based in the axiomatic adage “ex nihilo nihil fit”, i.e., nothing comes from nothing. It is admissible to synthesize the presocratic thought in such saying. The being could be one or unlimited, such as Anaximander’s apeiron, or multiple, such as Empedocles’, but the Greek thinkers – without exception – accepted without discussion that nothing would come from nothing and that the single or multiple principle of all things was the being.

Duns Scot very well pointed out such aspects later on when explaining that those philosophers could – as they would – discuss the essence or the characteristics of such being, but it was unanimous – at least in Western philosophy – the acceptance of a being – undetermined considered but still being as principle, source or beginning of all things.

One can say however that the metaphysical studies on the being was initiated amongst the Greeks by Parmenides, since until then such speculations encompassed only the “physical” field. It is true that amongst the Pythagoreans there were speculations about “the being whilst being”, but since there is major misconceptions about their philosophical activities we rather examine the Pythagorean metaphysics – mainly that of the teleitos level of initiation – in another opportunity (Pythagoras and the Theme of Number).

The gnoseological theory of Parmenides establishes a parallel between the order of being and the order of knowing – since “the entity is intelligible and the intelligible is entity”. Entity (to ón) corresponds to the latin ens, the id cui competit esse – that that compete the being, that that can be attributed to the being. To accept the intelligibility of the entity is to affirm the “rational principle of sufficient reason”.

Parmenides insistently affirmed in the fragments that remain that being is and non-being is not. He accepted only one entity, one being that is. Such aspects were discussed in our previous books and what must be emphasized is that he affirmed that entity cannot produce entity. And his arguments can be synthesized as follows. If there was more than one being, the second one would be distinguished from the first whether by what is entity or by what is not entity. Now, it could not be distinguished from what is not entity, for how can what is nothing distinguish something from something else? On the other hand, it could also not be distinguished by the entity, for the entity would identify with the first one and the difference would still be entity and could not be distinguished, as such, from the first one. If the entity would produce entity, it would only be affirming itself. Therefore, between being and non-being there is no place for an intermediary – Parmenides affirmed – which is a way to affirm the principle of identity that is attributed to him as the first announcer.

As a consequence, Parmenides ends up denying the “coming to be” and “passing away”, as well as all and any mutation. For how could a thing become what it already is? Becoming is the path to being, for all becoming is a becoming-a-being. And how could the being – that already is – become a being, if it already is? In such position, Parmenides found himself before a conundrum: if something becomes, it becomes whether from a non-being to a being or from a being to a being. The first option is impossible, for how can a non-being generates a being if non-being is nothing? And how could the being become being if it already is so? In such conditions, concepts such as mutation, becoming and production are inconceivable. And once only the being is intelligible, any becoming is unintelligible and does not exist. Thus he would exclaim: “thereby the fire of becoming is extinct perishing is banned”. If being is, perishing – a becoming from being to non-being – is not.

But how can one deny the testimony of our senses that affirm mutability? Clearly Parmenides knew that. However, he affirmed it all as appearances (phaenomenon), mere phenomena.

Now there is a reality that his philosophy could not save. Parmenides actualized the one and virtualized the multiple, which he sacrificed for the former without resolving the eternal and fundamental theme of all philosophy that always hovers over both antinomies, whether affirming one to deny another or trying great synthesis, as in Aristotle. Parmenides thought had a great influence in Greek philosophy. A solution between the One and the Multiple ought to done.

A solution emerged trying to explain multiplicity as follows: the being would be formed by particles of intrinsic immutability (parmenidean positivity of immutability of being), at times approaching, at times moving away, according to attractions and repulsions. From such multiple combinations emerged then the heterogeneity of existing. Heterogeneity was explained by homogeneity. Thus, being born (generation) and dying (corruption) would be merely products of their qualitative combinations within the being. Herein, Empedocles, Anaxagoras and the atomists Leucipo and Democritus agreed upon, diverging therefore from Aristotle.

Mutability as such could be mechanically explained. This conception is in general lines the overview of the Greek mechanicist thought, which was replicated in Aristotelian naturalism, imposed in light of aporias examined so properly by Aristotle.

Synthesis of the Greek Atomistic Thought

Aristotle examined the Greek atomism and reveal its aporias. Leucipo and Democritus remained loyal to Parmenides’ thought of intrinsic immutability of being. However, they affirm the opposite of Parmenides when referring to non-being. While he affirmed non-being as non-existing, the atomists affirmed nothingness as existent, therefore jumping into the negative – as commented by Joel. For them, nothingness is “something”, emptiness (vacuum, to kenon), the empty space. Such empty space exists and it is wherein moves indivisible particles – atoms (from a, privative alpha, and tómos, parts), unbreakable and intrinsically impossible to divide.

Thereby, generation (being born) and corruption (dying) of beings occur through rapprochement or separation (agregatio or desagregatio) of atoms. For both thinkers, atoms are not all the same, having different forms – however they are all immutable.


To fully comprehend the work of Aristotle, we shall now clarify the concept of mutation and its classifications. Mutation is the transference from one mode of existence to another. When it is a change in the substantial form, it is called corruption; when it acquires a substantial form, generation; when it goes from a certain quality to an opposite quality, it is called alteration (alteratio); when it goes from a place (ubi) to another, there is local, topic movement; when it happens from a smaller quantity to a larger one, increase (augmentum); in reverse, decrease (decrementum).

Mutation that happens to a substantial form (ad substantiam), is instantaneous. Mutations of alteration, increase and decrease are successive.

Local mutation is a mere modal – as studied in our Ontology.

Since a transit from a state to another, mutation can be intrinsic or extrinsic depending on the transit’s determination. Intrinsic mutation can be metaphysical or physical. Creation, transubstantiation and annihilation are of the metaphysical type.

Physical mutation is either substantial or accidental, when the formal term (terminus quo) is substantial or accidental. Substantial physical mutation can be either generation or corruption, when the ad quem term is a form or a privation of form.

Generation happens from a negative term of form to a positive one (for example, from a non-water to a water); corruption happens from a positive term to a negative, the transit of a form to its negation1.

Such mutations are instantaneous for between being and non-being – or between non-being and being – there can be no medium or distance.

Accidental mutation is either instantaneous or successive. It is instantaneous when it is accidental generation or corruption; it is successive, local mutation, alteration and increase.

On Generation and Corruption (Peri geneseôs kai phtorás)

The treatise On Generation and Corruption is placed in Aristotle’s series of works called Physiká (Physics), whereupon he studies motion in a general sense, such as mutation of any kind. Every movement can be considered according three terms:

terminus a quo (term of start); terminus quod (the movable) and terminus ad quem (term of finish)

Physics is the general introduction to further treatises and its object is the common traits of special objects from subsequent treatises, which are the Peri Ouranou where he summarily presents his world conception. In this book he also analyses the circular movement of the stars, the rectilinear motion of light and heavy bodies, as well as the specific form of the local (topic) movement, which is a specie of genre motion (metabolê).

In On Generation and Corruption, he addresses specific movement, which is the production and destruction of beings and their properties. Aristotle aims to demonstrate that generation of a being is the destruction of another.


1. Corruption comes from the Latin verb corrumpere (augmentative cum and rumpere, to break), meaning to break the unity or that that lost its form to decompose in its components.