For much-neglected common sense reasons:
We have all seen claims by neuroscientists that “the self is nothing but an illusion,” or that “free will does not exist,” or that “the mind and consciousness are nothing but brain activity, ” or, best of all, that “religion is a delusion, as it is nothing but brain mis-firings.” But from a neuroscientific perspective these extravagant claims are difficult to accept. When the data supporting such claims are examined in detail, they typically support much more modest claims, such as that “the sense of self is significantly associated with enhanced (relative to baseline conditions) ventromedial prefrontal brain activity,” or that “one aspect of religious cognition is associated with increased levels of dopaminergic activity in mesocortical dopaminergic circuits,” and so on.
In short, the “nothing but…” claims are really claims concerning brain activity correlates of some mental or cognitive process. The fact that any given higher cognitive process is associated with some change in regional brain activation patterns, of course, does not at all indicate that the regional brain activity pattern in question explains everything you need to know about that cognitive process.
The apparent thinking behind deflationary claims like “X is nothing but…” is that partial truths can fully explain larger, more complete and essential truths. But in most cases the essential truth concerns the whole, and wholes cannot be explained simply by decomposing them into their constituent parts. There is some reality and autonomy to each level of inquiry in any given scientific investigation or field. To state the obvious: water has something that hydrogen and oxygen molecules do not have when considered separately. A behavior, a cultural norm, a mental experience, and a cognitive process all have something that cannot be found when each phenomenon is decomposed into its constituent parts. The whole, particularly in the realm of behavior, is always greater than the sum of its parts.
Patrick McNamara, ““Nothing but…” reductionism is not good science: why I as a neuroscientist reject reductionism. ” at Society of Catholic Scientists
Keeps his job, we hope.
See also: Mike Egnor on why Coyne and Hossenfelder are wrong to deny free will. Egnor: Now let’s get to the neuroscience. Neuroscience has a lot to contribute to the debate over free will and all of it supports the reality of free will. There isn’t a shred of neuroscientific evidence that contradicts the reality of free will.