The tangibility problem is the challenge of demonstrating the difference between the tangible and the non-tangible. If a claim that there is a difference cannot be demonstrated, then all questions involving the "reality" of both tangible and non-tangible (non-physical, immaterial, intangible, etc.) "things" become indefinable enigmas. In other words, lacking a referent, non-tangible becomes meaningless and the difference moot.
Of course, everyone "knows" what the difference between tangible and non-tangible is. It's "obvious." That's part of the problem. If it's so obvious, then we can describe what constitutes the difference. Here I'm not referring to the definitional difference between the terms tangible and non-tangible. The definitional difference assumes an ontological difference in order to have any meaning. I'm interested in the ontological difference between whatever those terms refer to in "reality."
The tangibility problem has a twist to help preclude getting distracted with mere definitional concerns (which is why I used the cumbersome "non-tangible" instead of intangible--I know you nit-pickers are out there!
) The tangibility problem requires that, at a minimum, we describe how tangible is different than observable. Unless we can show that tangibility involves something more than amenability to observation, we have no reason to think that our notions of tangible, physical, or material are different metaphysically from the intangible, the non-physical, or the immaterial, because we have no reason to think that the difference refers to things rather than merely to the limitations of our ability to observe them. If the latter, then by virtue of our limitations we have no information about "non-tangibles" with which to make any claim about them, let alone to consider them as "less real" than tangibles. Instead of solving the tangibility problem, we inevitably assume that there is no problem, or that it has been solved. Of course, whatever naïve and unexamined concept of "tangible" (or "physical" or "real") we happen to prefer also just happens to be the "solution." Give it a try and see if it's easy. If it's been described so well, you should be able to recite a description by rote. Stating that there is a difference is not the same as describing what the difference consists of.
My suspicion is that the apparent "difference" between tangible and non-tangible is a trick of our minds. I suspect this because at any particular juncture, "tangible" corresponds very closely to those things that fall within the scope of our ability to observe, and "non-tangible" corresponds to anything outside those limitations, whether it eventually proves to be "physically real" or otherwise. As our observational technologies advance, we start to consider things as "real" that in the past would have been derided and ridiculed as imaginary or fantastic by every academy of science. Quantum entanglement or dark energy, for examples. For another, the role of "mental" processes to instigate and heal diseases and pain, (which are now well-established in case you haven't been keeping up,) IOW "mind over matter."
I suspect that our tangible/non-tangible dualisms are leftovers from days in which we believed that "spirit" (i.e., God) is a uniquely different "substance" (yeah, they used to use that term for non-tangibles, go figure,) which operated in a completely different "realm" than "physical" things in the "natural realm." I suspect that these dualisms are reifications of our own cognitive limitations that we attribute to "reality."
Glad to hear your thoughts. And to preclude complaints about over-generalization and caricatures, please. I'm talking about a meta-philosophical issue that I have observed during 40 years of study in both academic and other serious writing, one that cuts across all disciplines. Please focus at the level I'm presenting the problem.
Thanks!
