Aristotle’s Philosophy: Key Concepts Explained
1. Happiness
Happiness, for Aristotle, is the ultimate end or purpose of human life. It is not a passive state but an activity of the soul in accordance with perfect virtue, specifically the virtue of reason, exercised over a full life.
To define happiness, Aristotle considers the proper function of man. He identifies three functions of the soul: nutrition (shared with plants), sensory perception (shared with animals), and reason (unique to humans). True happiness, therefore, lies in the exercise of reason. This involves contemplating first principles, as studied in theoretical sciences like metaphysics and theology, and consistently choosing the middle ground between extremes.
Happiness is a perfect good, desired for itself, not as a means to another end. There are three types of goals: those desired for something else (like money), those desired for themselves and for something else (like honor, pleasure, or intelligence), and those desired only for themselves (like happiness).
Happiness is also a perfect and sufficient end, providing self-sufficiency. However, Aristotle acknowledges that it is enhanced by material comforts, creating a surplus of goods.
2. Nature (Physis)
The focus of physics is physis, or nature. For earlier philosophers like Thales and Anaximenes, physis was the fundamental material element. Aristotle adapted this concept to explain movement and change in natural beings. Physis is the immanent principle of substantial movement in these beings. According to his hylomorphic theory, physis is how matter is actualized. In other words, it is the internal cause of a seed becoming a tree. This theory is particularly suited to living things, reflecting Aristotle’s biologically-centered thinking.
For example, man is by nature a rational and social animal. This inherent mode of being defines human reality. Politically, man is naturally social. Ethically, human nature is distinguished by reason (logos). Therefore, fulfilling human physis means living in society and cultivating reason.
3. Social Being
Beings living alone are either gods or beasts. Man is by nature a social and political animal, inhabiting the polis. This is evident in our possession of language, which nature provides for communication and discerning right from wrong, just from unjust. Humans need society to fulfill their needs and exercise their rational function. Life is better in the community.
Autarky, or self-sufficiency, was considered by some philosophers as the supreme good. For Aristotle, while individual autarky is good, true autarky is achieved only within the political community. While happiness provides some individual self-sufficiency, true self-sufficiency resides in the polis. Humans are social beings, needing interaction with family, friends, and fellow citizens. Later, Hellenistic philosophers like the Cynics, Epicureans, and Skeptics equated happiness with individual autarky due to the perceived evils of the declining polis.
4. Substance
Aristotle observed that despite constant change, something remains unchanged in every object. This unchanging substrate, impervious to change, is substance. For example, water remains water regardless of its state (solid, liquid, or gas). Substance has inherent existence, the real foundation supporting all changing qualities (accidents), such as color, hardness, shape, and temperature.
Aristotle distinguishes two types of substances: primary substances (specific individuals like Socrates) and secondary substances (universal forms like “human”). Strictly speaking, only individuals are substances. However, since species and genera are also real, they are considered secondary substances, inseparable from primary substances.
Primary substance is composed of matter (hyle) and form (morphe), according to the hylomorphic theory. Form is the essence, the secondary substance or species, and is eternal. Matter, in the case of a man, is flesh, bones, and blood. This is proximate matter, perceived by the senses. Aristotle also posits prime matter, formless and indeterminate, recalling Anaximander’s apeiron or Plato’s primordial matter. This prime matter is also eternal but imperceptible, understood only by intellect.
Unlike Plato, Aristotle believes substance undergoes development and becoming (genesis), as seen in embryos. Thus, primary substance is not static but a dynamic reality capable of growth.
5. Cause
Scientific knowledge requires understanding an object’s causes. Physics seeks to establish the causes of natural things and their motion. Aristotle criticized earlier philosophers for focusing on only one cause, such as the material cause. He proposed four causes: 1) material cause (e.g., flesh and bones), 2) formal cause (e.g., human form), 3) efficient cause (e.g., parents), and 4) final cause (e.g., rational social animal). The formal, efficient, and final causes relate to physis, contrasting with the material cause. In living beings, the theory of causes aligns with the hylomorphic theory.
6. Potency and Act
Everything has two aspects: act (what it is) and potency (what it can become). Act has priority over potency. A seed, though chronologically prior, is oriented towards the act of becoming a tree. Aristotle held a teleological view of reality, where potency is directed towards its final cause.
Aristotle saw movement as a progression from potency to act, correcting Parmenides (who focused solely on act) and Heraclitus (who claimed everything constantly changes). Parmenides failed to distinguish being-in-potency from non-being, while Heraclitus neglected the stability provided by substance.
Potency and act parallel matter and form. Matter is potentially form, while form actualizes matter, giving it being. Form is always act.