THE SOUL OF THE MATTER
So how can we decide whether souls exist? Is this even a question about which science has anything to say? To many people, the answer to my second question is a resounding “No.” After all, science deals with phenomena that can be objectively observed and measured. The soul, by contrast, cannot be observed or measured because it is claimed to be immaterial. Therefore, soul beliefs belong to the realms of religion and metaphysics. This conclusion, however, is mistaken. The soul is a scientific hypothesis about the design and functioning of human beings (the stuff of biology, psychology, and neuroscience), and dualism makes claims about the detachability of mind and body and the existence of a substance capable of causal interaction with ordinary matter (the stuff of physics). As such, souls are fair game for scientific investigation, subject to the same criteria that apply to the evaluation of any other scientific idea (a line of reasoning developed more generally for other supernatural concepts by the physicist Victor J. Stenger in his book “God: The Failed Hypothesis”). After all, science can tell us what happened a fraction of a second after the big bang took place, some 13.8 billion years ago, when no one was around to make measurements or record anything. Is it so far-fetched that science would also have something to say about what we are made of and how we function?
Imagine an episode of “CSI: Miami” in which the investigators have a suspect and are beginning their forensic work. As they gather the evidence, they discover that the suspect has no serious alibi for the night of the crime. It also doesn’t take them long to figure out what could have motivated their suspect to kill his victim. Using more sophisticated equipment, they uncover physical evidence that links the suspect to the victim and to the crime scene—blood stains on the suspect’s clothes that match the victim’s blood type, DNA evidence that positively identifies the blood as that of the victim, soil on the suspect’s shoes whose chemical composition matches that of the soil at the crime scene. Our investigators are also able to get their hands on a recording of the crime scene taken by a surveillance camera at a critical time right before the crime, and using digital video-enhancing techniques, they manage to retrieve meaningful evidence. Aided by powerful face-recognition software, they are able to place the suspect at the crime scene at the right time.
When taken in isolation, few, if any, of the clues uncovered by our team of forensic experts are really incriminating. The soil on the suspect’s shoes could have come from a walk he took at the scene of the crime the night before the victim was killed. If the victim and the suspect knew each other, perhaps they spent some time together before the murder took place, and the victim, who was subject to frequent nose bleeds, ended up accidentally soiling the suspect’s jacket. Since the jacket was dark, the suspect didn’t notice the blood stains until after the police apprehended him the following day. As for the other pieces of evidence, I am sure that you can easily concoct a plausible story as well. It is when taken together, however, that all these disconnected pieces of evidence acquire their collective power, and as they accumulate, we soon reach a point where it is no longer reasonable to conclude that our hypothetical suspect is innocent.
The forensic-investigation analogy is a good one because it also captures the story of how mainstream science has come to the conclusion that human beings most likely do not have souls. One of my goals in this book is to present all the relevant pieces of evidence—from psychology, biology, neuroscience, philosophy, and the physical sciences—to support the conclusion that, when considered collectively, they undermine the soul hypothesis to the point of oblivion. Notice that the conclusion, if we want to be intellectually honest, should not to be that there is no soul, but rather, that there are no good reasons to believe that we have souls, and that there are very good reasons to believe that we do not have souls. To anticipate my conclusions, I will show you that the soul has shrunk as scientific understanding progressed, that there is no objective evidence supporting the soul hypothesis, that there is no known formalism that describes the soul substance, that souls fly in the face of what we know about modern science, and that no explanatory gain comes from postulating the existence of souls. In sum, I will show you that the soul has exactly the set of properties that it should have if it didn’t exist.
Just like other false ideas we entertained in the past had harmful consequences and stifled progress, so too, I will argue, do soul beliefs. In medieval Europe, during the Great Plague, people often had their lips sewn shut and their tongues cut off for fear that they would blaspheme and offend God. This was a perfectly rational practice, if brutally sadistic, based on a deeply flawed theory. Replace God’s wrath by the germ theory of disease and the sadistic practice loses its raison d’être. In less dramatic fashion, but in the same conceptual vein, I will show you that our soul beliefs get in the way of a more humane society. Our dualist intuitions lead to beliefs that cloud important societal debates, such as abortion, stem-cell research, and the right to die with dignity. Our intuitive notion of justice, and therefore our entire criminal justice system, which is unusually harsh and biased in the United States, as we will discover, may also be premised on dualistic assumptions. These enormously important issues that we face as a society should be approached armed with the best knowledge we have, not with traditional ideas that have no scientific credibility.
Through the pages of this book, I will lead you on a journey through science and thought to arrive at the following conclusions:
The traditional soul is as much a scientific hypothesis about our design and mode of functioning as it is a metaphysical or theological claim. Consequently, determining whether or not we have a soul is an objective endeavor that falls within the scope of science.
In spite of many claims to the contrary, there is in fact no credible evidence supporting the existence of the soul.
Modern science gives us every reason to believe that we do not have souls.
Nothing gets lost, morally, spiritually, or aesthetically by giving up our soul beliefs. In fact, we even have something to gain.
The scientific image of personhood, so feared and vilified in the United States, provides the basis for an empowering and practically beneficial alternative to the soul myth.