Humans have long theorized that we are more than the purely physical. Ancient Indian philosophers called our spiritual aspect atman. The Greeks called it psyche; the Romans, anima. But they’re just different words for what we would refer to as the soul.
The Bible explicitly references souls as our spiritual selves. In the First Epistle of Peter, Jesus is called the overseer of our souls. When the creation of man is described in Genesis, the text says that God formed man out of dust and dirt, and then he “breathed into his nostrils the breath of life; and man became a living soul.”
“In my view, the soul can actually be decoupled from the body,” says Joshua Farris, a professor of theology of science at Missional University and author of the book The Soul of Theological Anthropology.
According to Dr. Farris, when the Bible mentions the “soul” or the “spirit,” it’s using a literary device known as synecdoche, meaning a part is being used to refer to the whole. The soul is a part of the person, but it’s also the person. The language infers the meaning of the concept itself. “So, a person could exist disembodied because of the soul,” says Dr. Farris. Like we might in heaven.
But if the Bible refers to the soul as a separate entity, where is it located? What are its characteristics? Can these questions even be answered at all?
The ancient Egyptians believed that the soul could be found in the heart. Leonardo da Vinci thought it was located in the optic chiasm, near the third ventricle of the brain. The philosopher René Descartes’s writings place the soul in the brain’s pineal gland.
In 1907, a Massachusetts doctor tried to gain a better understanding of the soul through an attempt to quantify it.
In a now-infamous study, Duncan MacDougall devised an experiment to determine the weight of the human soul. The idea was that if the soul had a physical presence, there would be a difference in the weight of someone’s body before and after death. That difference would be the weight of the soul. To test this hypothesis, Dr. MacDougall constructed a bed fitted with a set of beam scales. Terminally ill patients who agreed to take part in the experiment would lie in this bed during their final moments.
MacDougall was meticulous in his MacDougall records, weighing his patients constantly during the process. He even attempted to factor for the fluid losses that typically take place during death. His conclusion was that the human soul weighed three-fourths of an ounce, or 21 grams. And while his findings have since been debunked, it’s still the first recorded effort of science trying to quantify the soul.
In the 115 years since Dr. MacDougall’s experiment, science’s search has continued. Many scientists are of the opinion that what some might consider the soul is the product of the chemical reactions and electrical pulses of our brains.
Sir John Eccles, the 20th-century Nobel Prize–winning Australian neuroscientist, disagreed. Acclaimed for his research into the central nervous system and synaptic transmission, the process in which the brain’s neurons send and receive messages, Eccles would go on to propose a different theory. While he agreed that the brain and the soul were connected via the cerebral cortex, he believed that it was the soul that influenced the brain. That all mental processes, including thoughts, memories and emotions, originated in the soul but were expressed as physical mechanisms in the brain.
While he was never able to find concrete proof to substantiate this theory, it was one he pursued all the way up until his death in 1997.
“I maintain that the human mystery is incredibly demeaned by scientific reductionism, with its claim in promissory materialism to account eventually for all of the spiritual world in terms of patterns of neuronal activity,” he wrote in his 1989 book, Evolution of the Brain: Creation of the Self. “We have to recognize that we are spiritual beings with souls existing in a spiritual world as well as material beings with bodies and brains existing in a material world.”
Some scientists believe that as we learn more about quantum mechanics, we’ll eventually discover the soul among quantum particles. Others insist that as technology improves, we’ll be able to see the soul in the electromagnetic waves that our brains generate.
“I don’t know if there’s ever going to be an empirical test that would demonstrate the soul’s existence,” Dr. Farris says. “There’s something about the nature of the soul and even the nature of consciousness that we can only ever arrive at indirectly.”
So what is the soul, and where is it? These are the questions science must keep asking, because that’s what science does. But we must also acknowledge that we may never uncover a scientific answer. Maybe we’re not meant to. At least, not in this life.
