Most major religions point to the existence of the soul. But while religious groups have long since taken the concept of the soul on faith, scientists refuse to do the same.

The Ancient Greeks (500-200 BC)

Ancient Greek philosophers are responsible for some of the first recorded treatises on the soul. Hippocrates believed that madness originated in the brain, while Plato described foolishness as a “disease of the soul.” Philistion went on to point out that foolishness had two parts: madness and ignorance.

Later, Pythagoras described a three-part soul that consisted of intelligence, reason, and passion. He believed that reason and intelligence were located in the brain, while passion was housed in the heart.

Aristotle outlined his thoughts on the soul in his treatise De Anima, or On the Soul. To Aristotle, the soul made a fully functional human life possible, but it was inseparable from the physical body.

Leonardo da Vinci (1452-1519)

Da Vinci was a genius whose ideas about the human soul were before his time. He wrote this about the soul:

“[Nature] puts there the soul, the composer of the body, that is the soul of the mother which first composes in the womb the shape of man and in due time awakens the soul which is to be its inhabitant.”

René Descartes (1596-1650)

Descartes was the first philosopher to call the mind and soul of a man as “entirely different” from the body. He claimed that the soul could be found deep within the brain, in the pineal gland.

Lancisi (1654-1720)

Lancisi was in agreement with the idea that the soul could be found in the brain, but he believed it was housed in the corpus callosum. His theory pointed to the “vital spirits” flowing within the corpus callosum, forming a pathway between the seat of the soul and the peripheral organs.

Thomas Willis (1621-1675)

A Professor of Natural Philosophy at Oxford University, Willis believed that studying the anatomy of the brain was the only way to unlock the secret of the soul.

Dr. Duncan MacDougall (1866-1920)

In 1907, MacDougall tried to pinpoint the weight of a human soul by weighing a human being before and after death. Based on six patients, he determined the soul weighed between 0.5 and 1.5 ounces.

Otto Rank (1884-1939)

Rank, a disciple of Sigmund Freud, believed that the search for the soul grew out of mankind’s insecurity with the idea of immortality.

Modern Skeptics

Some modern-day scientists dismiss the idea of the soul altogether. V.S. Ramachandran (b. 1951), a University of Chicago brain scientist, once said that the concept of the soul is “complete nonsense” on par with superstition.

Other scientists say that science will never be able to address the soul. Kenneth R. Miller, a biologist at Brown University, said that the soul is “not a scientific idea,” and it’s therefore pointless for scientists to try to address it.

Today: Are We Any Closer to Finding the Soul?

Other researchers have come to the soul’s defense. Among them is Oxford philosopher Richard Swinburne, who argues that it’s incorrect to call the body and the brain merely physical things. The soul is an essential part of the human experience.

But so far, science doesn't seem to be any closer to proving the existence of such a soul. We may know from experience that we're more than a mere combination of physical particles, but we aren't any closer to proving it.

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