All the metaphysical discussion as of late on this blog has left my mind racing on many things. Yet, one thing I felt in particular that needed to be tackled was the epistemological framework known as Model-Dependent Realism (henceforth MDR). This epistemology is a favorite of Mike D over at The-Aunicornist. Frankly, I get quite tired of having this idea thrown around when it is so blatantly ridiculous, and thus I felt the need to demonstrate such.
So, let us first expound this epistemology—only to be found promulgated in The Grand Design by Stephen Hawking, which should already make said epistemology suspect, since the book is, to be blunt, quite terrible.
[O]ur brains interpret the input from our sensory organs by making a model of the world[…] If two such physical theories or models accurately predict the same events, one cannot be said to be more real than the other; rather we are free to use whichever model is most convenient.
There is no picture-or theory-independent concept of reality. […] These mental concepts are the only reality we can know. […] [A] well-constructed model creates a reality of its own.
It should be obvious upon first glance how extreme and ridiculous MDR is. It is an amalgam of previously known philosophical positions such as pragmatism, constructive empiricism, and some type of idealism—all, at least to me, untenable philosophies in themselves.
Nothing is “real”, except my theory
Probably one of the most extreme promulgations in MDR is that one’s “model” cannot be said to be more real than another’s. This is pure nonsense. First, let it be understood that MDR does not claim that if two theories can both accurately describe or predict the same observations, then we cannot, at the moment, determine which theory actually conforms to objective reality. No, MDR is claiming that neither theory conforms to reality more than the other—that is, neither theory is more real than the other.
To illustrate the depravity of such a position, let’s take two well-known models of reality: realism and solipsism. The realist states that an objective reality exists independent of observers, while the solipsist states that only his mind exists. Surely these models are mutually exclusive, and either one or the other has to be predicated of reality—that is, either only I exist, or a reality exists which I am a part of; there is no middle ground here. However, on MDR we cannot say that one is true while the other is false. Rather, neither is true. Yeah…this is the intelligence blooming from the mind of Hawking, and this is why Einstein said, “the man of science is a poor philosopher”.
That being said, MDR has much bigger problems than this. You see MDR, though denying the objective reality of theories, must uphold the reality of at least one theory to be valid. Remember the following foundational claim of MDR: There is no picture-or theory-independent concept of reality. Now, is this assertion true or false—that is, can it be predicated of reality, or not? If so, then MDR has just made an objective claim about the nature of reality, the very thing it claims cannot be done. If not, then MDR is false. Either way, MDR refutes itself.
Pragmatic, for whom?
Remember that MDR asserts that if two models of reality are equally on par at describing our observations, then we can use whichever model we find most valuable or convenient. This is pure pragmatism—and MDR, just like any philosophy founded on pragmatism, runs into problems because of this. First, if one can adopt any model based on its utility, then the validity of models is subject to the whims of individuals. For what’s pragmatic for me will not necessarily be pragmatic for you. But wait. I personally find it ridiculous, and therefore, not pragmatic, to hold to MDR; and my worldview, which excludes MDR, makes the same observations of reality as any other. So, since it is convenient for me to reject MDR, then, on MDR, I am free to do so and no one can claim that what I have done is invalid. Thus stated, MDR has led to the rejection of itself!
Second, MDR again pulls the rug out from underneath itself. Pragmatism is a theory of truth which explicitly rejects the correspondence theory of truth—i.e., a statement is true if it corresponds to reality. But, the only way to do this is to make an objective claim about reality—that is, truth as such is illusory. However, to make such an objective claim is to go against MDR—which rejects objective claims. MDR once again must do the very thing it claims cannot be done.
There are many more problems with MDR, but I do believe its untenability has hitherto been demonstrated. Advocates of MDR seem to make their case solely on the basis of how our sensory organs take in datum and relay it to our brain. This seems, to them, to demonstrate that only the appearance of reality is accessible to us, as opposed to reality in itself. But, notice that this is once again an objective claim regarding what really goes on when we abstract concepts from the observed. More importantly there are many epistemologies out there that take such cognitive facts into account while still proclaiming that reality in itself can be known. And who are model-dependent realists to say they’re wrong? They can’t, because their epistemology doesn’t allow them. On the contrary, it is much more convenient to affirm an epistemology that promulgates the reality of the observed, and therefore we see one more instance of MDR shooting itself in the foot.