Thales of Miletus and his Thoughts on the Universe

Who are we? Where do we come from? Where are we going? Thales of Miletus, considered the founder of natural philosophy, was the first person to ask these questions.
Thales of Miletus and his Thoughts on the Universe
Gema Sánchez Cuevas

Reviewed and approved by the psychologist Gema Sánchez Cuevas.

Last update: 10 September, 2024

Thales of Miletus (c.624 BC – c.BC 545) founded the Ionian school of the ancient Greek thinkers. Furthermore, at that time, he was known as one of the seven sages. Even Aristotle himself came to regard Thales as the founder of natural philosophy. This was because he was the first Greek to search for the ultimate principle of everything. He considered this to be water.

Thales lived in Athens. Some texts suggest he was educated by an Egyptian priest. He was deeply involved in astronomy-related problems. He provided a series of supernatural explanations for certain cosmological events.

In the end, his philosophical approach, which meant he questioned everything about the celestial, led to the start of Greek astronomy.

The Earth from Space.

Talus’s hypotheses were bold and new. The Internet Encyclopedia of Philosophy (IEP) states that he may well have been the first to study astronomy, the first to predict eclipses of the sun, and the first to set the summer and winter solstices.

Although he had no laboratory, no test tubes, and no instruments, he was the first to ask the question: Who are we? Where do we come from? Where are we going?

Now, let’s enter the mind of this great philosopher known as “The Wise Astronomer”. He left many sayings for us to reflect and meditate upon. To think of our place in the infinite space of the cosmos and our intimate relationship with it.

Thales said “Water is the first principle of everything”

Thales said that we’re made of water and we come from water. In fact, for him, water was nature itself, and the source of all things. It was the originating principle, the beginning of the universe. At the time, he believed that the Earth was a flat disc floating on water.

Furthermore, he considered that everything comes from water and, finally, that everything goes back to water. He believed that everything in the universe was simply a modification of water.

Thales thought that water was a unique substance. In 2009 a study was conducted on the nature of water entitled “The Nature of Water: Thales’ Arkhe”.

This study suggested that many explanations can be given about the importance of water for living processes. Thales thought, in the tradition of Homer, that Oceanus and Tethys were the forefathers of the world.

Even we humans are composed of 60 percent water. Furthermore, the brain is 70 percent, blood 80 percent, and lungs are up to 90 percent water.

“Space is the greatest thing as it contains all things”

Tales might not necessarily have considered space to be infinite. However, he did consider that it contained everything. He tried to explain the structure of the universe logically. He stated how far the Earth was from other celestial bodies like the moon, sun, and stars. To do this, he used Babylonian science.

However, much of his thinking was wrong. He considered the universe to be in reverse order. Because he claimed that the sun was further away than other stars.

“Isolate yourself in your inner world and reflect on the system of the universe”

By previous lines of thought, Thales proposed that we look inward. We should reflect on who we are, or what we want to be about the vast and immeasurable universe we live in.

Because if, as humans, we’re unable to comprehend the size and age of the cosmos, where do we think the minuscule home we call Earth fits in? Indeed, where are we amid such immensity and eternity? When you think about this, your usual daily concerns and worries seem ridiculous. Carl Sagan confirmed this.

Thales said, “God is the most ancient of all things, for he had no birth”

This saying from Thales reflects on the creation of the universe and the origin of everything. As the IEP suggests, Thales considered all things to be filled with God. The IEP states that Aristotle claimed:

Thales, too, to judge from what is recorded of his views, seems to suppose that the soul is in a sense the cause of movement since he says that a stone [magnet, or lodestone] has a soul because it causes movement to iron. Some think that the soul pervades the whole universe, whence perhaps came Thales’s view that everything is full of gods.”


All cited sources were thoroughly reviewed by our team to ensure their quality, reliability, currency, and validity. The bibliography of this article was considered reliable and of academic or scientific accuracy.


  • The Nature of Water. De Santo NG, Bisaccia C, Bilancio G, Romano M, Cirillo M. The nature of water: Thales’ arkhe. J Nephrol. 2009 Nov-Dec;22 Suppl 14:98-102. PMID: 20013740.

  • Internet Encyclopedia of Philosophy (IEP)

  • Divulgamat: Universidad Pedagógica y Tecnológica de Colombia, uptc.edu.co 


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