The most fundamental question of all human thoughts can be about us (human beings) and the world we live in. How did the universe come into being, or what is its most basic substance? Even though we think the answer belongs to the realm of sciences nowadays, seeking the nature of the universe has been the essential activity of Philosophy since its birth. Even now, philosophy can be a fundamental tool for integrating all scientific knowledge into a single grand system of thought.
The Early Greek Philosophers
“What is the original stuff from which all things come?”
Thales (Miletus)
- Everything comes from water and, in the end, returns to water.
Anaximander (Miletus)
- The original stuff is a living mass that filled all space. It is called “the infinite” or “the boundless“.
- At first, the infinite was whole, but it contained motion. The motion broke down the single mass into pieces with time. As the motion continues, all pieces eventually would be brought back to a whole.
Anaximenes (Miletus)
- The original stuff is air. Air becomes wind, clouds, water, and earth.
“In what way are the many things in the universe related?”
Pythagoras
- Things in the universe are related in ways that can be stated by numbers.
- The numbers became entities and things.
“Changing or Not”
Heraclitus
- Everything is constantly changing, and change is the fundamental characteristic of the universe.
- Fire must be the original stuff, since fire is never still and forever changing.
- The universe is ruled by “strife.” All things are changing all the time, and there is nothing permanent.
Eleatics
- The change is impossible. Nothing can possibly change.
- Xenophanes: The universe is a solid mass, which is forever unchangeable and unmovable. The parts may change, but the whole remains unchanged.
- Parmenides: If there is a change, something must come from nothing, which is impossible. Therefore, any change is inconceivable.
- Zeno of Elea: He is known for a number of ingenious paradoxes.
- For the paradoxes, look at The Eleatics
Empedocles
- The reconciliation of Change and Permanence.
- The universe is composed of 4 root elements: earth, air, fire, and water.
- There are many particles of each element, and they combine in various ways to form many things in the universe.
- In the strict sense, there is no change. The elements never change.
- But by mingling (Love) and separating (Hate) of elements, the things in the universe change all the time.
Anaxagoras
- The universe consists of root elements (substances), but not just 4. There are a lot of numbers of elements.
- Ex) Flesh consists of millions of particles of a flesh element. Bone is made of millions of bone particles.
Atomist (Leucippus, Democritus)
- Atomists agreed that the change is the result of the mingling and separating of tiny particles. But they disagreed on the nature of particles.
- Empedocles and Anaxagoras thought the elements differed in quality.
- Atomists said the root elements (atoms) were similar in quality but had different hooks or shapes. Atoms combine in different numbers and ways to form different things in the universe.
- Atoms are eternal, never change, and are all alike. The only change is how atoms group together.
Plato
The universe is the realm of perfect and unchanging ideas. Humans live in a shadow world that was created by impressing the perfect idea upon matter. All imperfections came from the fact that it was impossible to impress perfect ideas upon matter perfectly.
Shadow World
- The world we experience with our senses is not real.
- The experiences of our senses are the reflection of real things.
- The existence of the world we experience is the influence of the world of ideas upon matter, or the impression of the real world upon matter.
- The world of our senses was created by the “Demiurge,” who brought the ideas and the matter together.
Real World
- The real world is the world of ideas.
- The idea or form is eternal, never created nor destroyed.
- All ideas are arranged in order, the idea of perfect goodness at the top.
Aristotle
“How can perfect ideas be impressed upon matter?”
- Aristotle tries to mediate the theory of Atomists (material) and that of Plato (Idea).
- Both ideas and matter exist in the real world.
- Ideas (forms) are in things. Ideas and matter are always together.
Please look at Aristotle’s teleological worldview.
Scriptorium 
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