Science tells us that the brain and the mind are different only in that the brain is the physical organ and the mind is a word we use to describe a function or product of the brain. The mind/brain relationship is not unique. For example, our voice is a result of our physical bodies—without our bodies, there would be no voice. The voice, like the mind, is a word we use to identify the immaterial product of a collection of physical systems in the body. Other possibilities surround the general theme that the mind can exist independently of the brain. This is commonly seen in religion, spirituality, and science-fiction. The most common version of this theme favored by religions is that the brain acts as a receiver that temporarily holds the mind, but the mind can be "released" after death and even at will (think astral projection). How do we know which view is more likely to represent reality? For every phenomenon, we can posit a natural explanation or a supernatural one. As we explore the issue using science and reason, we collect evidence for and against each explanation. As we learn more about the human brain, the evidence is overwhelmingly in support of monism (the mind is not separate from the body) rather than dualism (the mind is separate from the body).
It is difficult to imagine how a mind can result from matter, or as it is often said, "molecules in motion," but it's also difficult to imagine how wetness can result from hydrogen and oxygen—two dry gasses. Everywhere in the universe we see the phenomenon of emergence that demonstrates that the whole is more than just the sum of the parts. Traffic is not a material thing—it is an emergent property of many cars being driven closely to each other. Waves are more than just the molecules that make up water; they are an emergent property of the interaction between molecules and an environment. Likewise, the mind is an emergent property of the brain. To insist that the mind has to "go somewhere" when the brain stops functioning is special pleading; because we clearly don't imagine afterlives for wetness that evaporates, traffic that dissipates, or waves that disappear on a calm lake.
Science has demonstrated unambiguously that changes in the brain affect the mind. From simple chemical alterations such as intoxication due to alcohol, to complex surgical or magnetic brain stimulation with the patient awake. For example, neuroscientist Michael Persinger was able to evoke a "sensed presence," in the feeling of a proximal sentient being, in a laboratory setting using magnetic stimulation to certain areas of the brain (Persinger & Healey, 2002). Time changes the brain, as well. When we are children, we have the minds of children. When we are adolescents, our raging hormones are strongly correlated with our thoughts and behaviors. As we go from childhood to adulthood, our mind develops, and these developments can be mapped to physical changes in the brain, mostly in the prefrontal cortex. Unfortunately, some of us will be fated to lose our identity to Alzheimer's or other similar neurological diseases that slowly destroy our brains and at the same time, wipe away our minds. One with a dualistic view can posit that our minds exist in some idealistic form, and are just limited by our brains... sort of like a governor they put on the go-karts at amusement parks to keep kids from having real fun. Not only is this pure speculation, but it degrades humanity by seeing the human body as a temporary nuisance to our mind rather than the precious source of the mind that it actually is.
Many people have claimed to have visited other "spiritual" realms, that is, they claim that their minds have left their bodies. Some people claim to have been reincarnated—the claim that their mind has occupied several bodies throughout space and time (strangely, about half of them were all Cleopatra). None of these claims has ever been demonstrated to be anything more than the result of a mind still inside the brain that produces it. If you want to hear more on this topic, be sure to listen to the episode I did on personal experiences.
The mind being a function of the brain is a scientific fact in that overwhelming evidence supports that conclusion and no scientific evidence refutes it, outside of the possibility of a handful of flawed studies or the inevitable statistically significant and probable findings due to the sheer volume of research in the area. It is our desire for immortality that blinds us to both evidence and reason while holding on to the idea that the mind is eternal (or at least immortal). However, dualism is not a scientific idea based on evidence, but one believed on faith. So if you have faith in dualism and can't or won't let go of the idea of immortality, then just why not just have faith in the idea that you can still be immortal even though your mind is a function of your brain. Giving up the idea of dualism may not have to mean giving up your religion or even the belief in an afterlife; you may just have to do some fancy reinterpreting.
Reason: Book I - A Critical Thinking-, Reason-, and Science-based Approach to Issues That Matter is based on the first two years of The Dr. Bo Show, where Bo takes a critical thinking-, reason-, and science-based approach to issues that matter with the goal of educating and entertaining. Every chapter in the book explores a different aspect of reason by using a real-world issue or example.
Get the book, Reason: Book I - A Critical Thinking-, Reason-, and Science-based Approach to Issues That Matter by Bo Bennett, PhD by selecting one of the following options:
Enroll in the Daily Doses of Reason Online Course. This is passive course where you are sent one lesson per day by e-mail. There is no required interactivity. Each lesson averages just a few minutes.
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