Aristotle's Core Philosophical Ideas: Reality, Change, and Causality

Introduction to Aristotle's Philosophy

Aristotle criticizes the Platonic Theory of Ideas. While Plato defended Ideas as essences, known to be intelligible things in the world, Aristotle did not entirely reject the concept of Ideas. Instead, he denied their separate existence, proposing that ideas are immanent, inherent in the things themselves. What Plato called 'essence', Aristotle often referred to as 'form' or 'substance' within the particular.

Aristotle's Ontology: Theory of Reality

Plato had contemplated the solution to the enigma of reality, which he divided into two worlds: the intelligible (the Ideas) and the sensible (physical things). Aristotle also proposed an explanation of reality, making a distinction between what he called 'First Philosophy' and 'Second Philosophy'.

• First Philosophy (Metaphysics) studies pure act, such as the divine or the Unmoved Mover.
• Second Philosophy (Physics) is dedicated to studying individual substances, particularly natural beings.

Physics: Natural and Artificial Beings

Aristotle distinguishes natural beings from artificial beings:

• Natural beings are those that exist in nature and possess an internal principle of motion and rest. They are distinguished into two types:
  • Animated: Possess a soul (e.g., people, animals, plants).
  • Inanimate: Do not possess a soul or life (e.g., air, stones).
• Artificial beings are produced by human beings and do not have an inherent principle of motion (e.g., a bed, a table).

Change: Substantial and Accidental

All beings, whether natural or artificial, exist either per se (as a substance) or per accidens (as an accident). Substances are independent entities (e.g., John, a chair), while accidents are qualities that exist in another (e.g., 'gray,' 'gray-haired,' 'wise' – as in 'John is wise').

Aristotle identifies two kinds of change:

• Substantial Change: A substance disappears, and another arises in its place (e.g., a piece of wood burning and turning into ash).
• Accidental Change: The substance remains, but its accidents vary (e.g., a person becoming fatter).

Matter and Form (Hylemorphism)

This theory, known as Hylemorphism, posits that every physical substance is a composite of matter and form.

• Form: The essence of a thing, that which makes it what it is. It cannot exist without matter, as it is only actualized in matter.
• Matter: That out of which something is made. It is potentiality, and when combined with form, it makes the subject concrete. Matter itself is considered eternal.

Aristotle's Four Causes

Aristotle distinguishes four causes that explain why something is the way it is:

• Material Cause: That out of which something is made (e.g., marble for a statue).
• Formal Cause: That which determines the matter, the form or essence (e.g., the shape of David for a statue).
• Efficient Cause: That which brings something into being, the agent (e.g., the sculptor Michelangelo).
• Final Cause: That for the sake of which something is done, its purpose or end (e.g., to create beauty).

Among these four causes, Aristotle considered the final cause to be the most important, stating that everything has a purpose.