I've recently encountered many people who are otherwise very intelligent, but who, for one reason or another, came to believe very foolish things, like libertarian free will, or that we have a soul. It's not that they're stupid or anything, it's mostly due to them just lacking information or having the wrong information in the subject matter, and/or are suffering from poor reasoning skills.
Knowing how to think critically is absolutely essential to being a rational person. We hear numerous claims everyday. But how do we make sense of them? How do we evaluate whether there is any truth to them or not? Well, the answer is long, and I'm in no position to give a full assessment of all the relevant factors. But I can outline a few very important things everyone should know when evaluating the validity of a claim.
Let's start with the claim that the soul exists. By 'soul' I don't mean anything in the metaphoric sense. I'm talking about the traditional notion of a soul, the kind that Descartes believed in: the invisible ghost that resides in our bodies, that animates us, and gives our intellect. This is a belief mostly left over from religion, but is still believed by a surprising number of educated people today. One way to evaluate a claim like this is to ask yourself,
if it were true, what would have to be the case? In other words, if souls were real, what would have to be the case logically and scientifically? Let's explore this.
If souls were real, it would have to be the case that the immaterial substance that made up the soul—whatever it is—had to be able to overcome the natural forces in and between the atoms that make up your body. That means there would have to be
extra forces at work that apply to the atoms in your body that
do not apply to the atoms that make up inanimate matter, like rocks. This echos a view once popular among philosophers and biologists until the end of the 19th century known as
vitalism. On vitalism there is something fundamentally different about living things and non-living things. Living things have a life energy that non-living things don't. This would have to be the case—at least for humans—if souls exist.
But the relentless progress of science has shown that this is
not the case. There
are no special forces or energies that exist in living things that non-living things do not have. There is no life energy out there, despite what all the Deepak Chopras of the world insist. Vitalism has been utterly discredited as an accurate description of reality. All the particles that make up you and I and rocks and trees are made up of the same three things — protons, neutrons, and electrons, that's it. And all the forces that govern them are the electromagnetic force, and the strong and the weak nuclear forces. Gravity is the forth force but is really not a force, it's the curvature of spacetime. Those are the fundamental components that make up everything in your everyday experience and there is no room for anything else. This information has just not gotten out there into the popular understanding of science, but in time it will. The bottom line is this — we fully understand the particles and forces that make up you and I and rocks and trees and planets and there is no room for anything else that can have a causal impact on the atoms that make up your body, like a soul. That is one idea that science has falsified, and we know this through the proper way of reasoning about claims by philosophizing on what would have to be the case if the claim were true.