How past civilisations searched for the soul

The soul. We all have opinions on what it is: the part of our brain that gives us our identity, our nature, the element in our natures that responds to music and love, the thing we seek to soothe and explore when we meditate.

But Barakat, in the second series of Tumanbay on BBC Radio 4, wonders not just what the soul is, but where it resides. Is it in our brains, our heart, or the solar plexus? The extraction of the soul has occupied civilisations for centuries – here are some of the ways in which our predecessors investigated it…

The Renaissance

In 1515 Leonardo da Vinci took a direct approach: wanting to prove his belief that the soul was to be found in the centre of the head, he dissected someone’s brain. This provoked a scandal and he was declared to be a sorcerer. French surgeon Gigot de la Peyronie and the philosopher René Descartes also believed the soul to be located in the brain. Descartes located it precisely in the pineal gland in the middle of the forehead and called that "the seat of the soul" – the location of the pineal gland is where other faiths and spiritual healers refer to "the third eye".

1900s

In 1907, American doctor Duncan MacDougall conducted experiments just before and after death, weighing the bodies of dying tuberculosis patients to see if there was any change in weight, which he concluded would be the soul departing the body. There was a change – 21 grams. This was used as the title of a 2003 film iabout a heart transplant.

The Tudors believed that the souls of those who had lived unhappily or immorally would become trapped after death. On All Hallows Eve, women would make soul cakes (little spiced biscuits), and children, in exchange for a cake, would pray for a soul in purgatory.

North American Shamans

Shamans in North America believe that we lose bits of our soul as we go through life, and shamans can work with the soul to replace it and make it whole again. This process is still offered by shamans working today.

The Germans believed that souls were born from, and returned to, sacred lakes. In fact the modern English word "soul" comes from Old Saxon – sêola, where sêo meant “sea”. It first appears in Beowolf in the 8th Century.

The Torah

According to the Midrash, a commentary on the Torah from around the 2nd Century AD, the soul is located in a bone called the luz, the bone either at the top of the spine or the coccyx, depending on the tradition.

Philosophers

By the 1st Century AD, anatomists such as Rufus of Ephesus had a firmer grasp of where the soul might be. Or at any rate, what was inside the head. The Roman physician Galen declared that mental activity occurred in the brain and not in the heart, which is what Aristotle had suggested. Galen believed that the brain was the seat of the soul; mind you he also thought that the brain was made of sperm.

Avicenna, a philosopher, developed his own theory on the soul, and to explain it created a thought experiment – the “Floating Man”. This required a person to imagine themselves floating in the air, not touching anything and as “out of their own body” as possible. He argued that if you could still feel and think, that was proof that self-consciousness existed without any need for physical presence; and that therefore, self-consciousness was the soul.

The question of the soul is largely left out of ethical debates about life support and medical issues in Western medicine, but as transplants – not to mention artificial intelligence – become more a part of our lives, what our soul means to us is going to become the next big question.