What is movement according to Aristotle?

The problem of becoming generated great debates in Greek philosophy, especially among the pre-Socratics. And to better understand the nature of movement according to Aristotle, we must review what his predecessors thought about it.

On the one hand, the Eleate School, whose main philosopher was Parmenides, claimed that motion was an illusion. While Heraclitus, the main philosopher of the Ionian School, believed that our world was constantly changing.

Plato believed that the sensible world, besides being changeable and corruptible, was only a copy of a perfect and unchanging world: the world of ideas.

For Aristotle, the sensible world was not an imperfect copy of a higher world, nor was it illusory; change was real, it did not need to be denied, as Parmenides did, nor should it be understood as the essence of reality.

To support his theses, Aristotle developed a science called Physics (or Second Philosophy) whose main objective was to explain all the complexity of sensible reality, as well as the nature of movement.

What will mark Aristotle’s philosophy is precisely this “valorization” given to the sensitive world. With him, the sensitive world becomes the source of all our knowledge.

Physics: the science of being as mobile

For Aristotle, Physics was the science that studies being as mobile. The central object of this science is everything that is capable of change, that is, the sensible substance. It differs, therefore, from Metaphysics, which studies being as being and suprasensible substance.

What is movement according to Aristotle?

Aristotle explains the movement and change of things by the concepts of act and potency.

For the Stagirite, all movement is a passage from potency to act. Potency means an intrinsic possibility of a being, and when this possibility is actualized, we can say that this being in potency is now a being in act.

A yellow car, for example, has the potency to receive the color red; once painted, it will be a red car in act.

For a potency to be realized, another being in act is necessary, which will act as an efficient cause.

Parmenides believed that all change implies a passage from being to non-being. Aristotle refutes this by stating that, in fact, change simply presupposes a passage from being, to another form of being.

The movement types

When we talk about movement, we usually think of local movement; in fact, this is one kind of movement, but not the only one. In philosophy, motion (kinesis in Greek) means any change that a being undergoes. And according to Aristotle, there are 4 types of motion:

1. The local movement (translation): which is precisely the change from one place to another.
2. The qualitative ( alteration): when a being gains or loses a quality, for example, when the car loses its green color and gains a red one; or when a healthy person becomes ill.
3. Quantitative: when a being suffers an increase or decrease.
4. Substantial mutation (generation and corruption): when the transformation of a substance into another substantially different substance occurs, for example, when water changes from a liquid to a gaseous state; or when a living being dies.

Matter: the foundation of all movement

Only the substance composed of matter and form is capable of change, because matter is the principle of potentiality and movement. Every being that has matter, necessarily has potency.

Only the substance composed of matter and form is capable of change, because matter is the principle of potentiality and movement. Every being that has matter, necessarily has potency.

That is why the unmoved mover, which is pure act, does not have the material principle.