If I were putting my faith in science, I would say that there will someday be enough evidence to prove whether or not we have free will. Instead, I’m saying that there may someday be enough evidence.
I agree that one can’t see the spiritual realm directly. However, one might be able to see the spiritual world indirectly, since spiritual causes have physical effects. If we find physical events in the brain that are outside reasonable quantum probability and physical laws, then we know that there is something spiritual directing those events. If we find that the brain is entirely deterministic from physical laws, we will know that there is no free will.
Or we may be limited in what we can observe. Who knows?
Several points need to be considered in addressing the issue of whether there can be a reductive scientific explanation of the mind as nothing but brain activity.
(1) What has to be done is to relate first-person data (the data of inner personal conscious life) with third-person observed scientific physical data. How do objective, publically-observable neuronal events produce/become inner, first-person conscious experience(s)? We need to be mindful that what we are trying to explain is the first-person data.
(2) We already know causality between brain and mind is bi-directional, i.e., not only can one affect conscious experience and functioning by changes in the brain, one can also affect brain structure and functioning by conscious changes in activity. Research into neuroplasticity has made this abundantly clear.
(3) As for spiritual causes and physical effects, we need to acknowledge that the interaction of the mind (soul, “spiritual realm”) with matter may only be ascertainable by the intellect and not by measurable physical changes/processes.
In many significant cases the intellect can grasp certain realities not apprehensible by the senses alone. Examples would be existence, causality, the epistemological justification of the scientific method, mathematical theorems, and the intuitive grasp of the principle of sufficient reason, the mutual ordering of parts in a whole. E.g., the reception of raw sense impressions on sense organs of itself does not contain the judgment that a particular thing exists or that one thing is a cause: it is an act of the intellect which judges that a thing or property exists.
“cognitions which are only sensory are not the result of principles and causes but of the sensible object itself acting upon the senses.
For to proceed from causes to effects or the reverse is not an activity of the senses but only of the intellect.”
[St. Thomas Aquinas, *Commentary on Aristotle’s Metaphysics, VI, Lesson 1, 1146]
(4) There are are serious questions as to whether the structure and function of physical objects type of analysis in science can ever bridge the explanatory gap between observed physical processes and inner first-person experience. Many researchers acknowledge that we have to settle for
correlation not reductive causation.
Joaquín M. Fuster, MD, PhD, a neurological researcher writes in his
Cortex and Mind. (Oxford University Press, 2003)
“There are evident correlations between the brain and the mind. In the domains of scientific empiricism, however, where causality reigns supreme, correlation is Cinderella. Yet correlation is the only logical relationship we can substantiate empirically between the brain and the mind. . . . correlation is all we need for upholding the indissoluble unity of cortex and mind.” (p. viii)
“A cognitive order, no matter how it is construed, cannot be causally reduced to a brain order. Only a semblance of causality can be indirectly inferred, for example, from the psychological effects of brain lesions or chemicals.” (p. viii) This is because “No cognitive function has a fully dedicated cortical area or network.” (56)
