Basics of Presuppositionalism. What is a Presupposition, exactly?

One of the most voiced criticisms of presuppositionalism is that it "assumes what it is trying to prove." In other words, some say, it is a "circular" argument. These seem to stem from the mistaken belief that a presupposition is something that is merely assumed, either a non-proveable assumption, or something akin to an axiom. 

Let's take each of these starting with the "assumption" claim.  

First, presuppositions are not taken to be synonymous with "merely assumed."  As used in presuppositionalism -- as Greg Bahnsen emphasized -- presuppositions are the basic, non-negotiable claims of a worldview. Also, a presupposition is a necessary belief to account for a "state of affairs."  Neither of these carry the notion of "unprovable assumptions."   In fact the characterization as a "necessary belief" carries with it the idea that such a presupposition is necessary because of the impossibility of the contrary, i.e. to deny it proves it by leading to self-contradiction.  That is the essence of proof used in TAG (the "transcendental argument for God").

We note that the charge of circularity used by opponents is a case of special pleading on their part.  They argue as if their worldview is not guilty of the "sin" of circularity.  Yet their argumentation is circular in the most vicious sort of way.  The most glaring example is the belief in the existence of an unproved disembodied universal abstract logic existing someplace in a materialist cosmos (or just as incoherent a platonic "heaven").  As Bahnsen pointed out it is unprovable on the basis of their presuppositions, citing the example: "How could one prove 'modus ponens' without using 'modus ponens'?"  One can't.  In other words, one has "modus ponens" because of "modus ponens"  -- one can't get more tightly circular than that.

To elaborate, here is a more immediate example from linguistics that illustrates the use of presuppositions in the presuppositional approach of Van Til: "Have you stopped beating your wife?" That question presupposes that the person did in fact engage in wife beating. That is the necessary presupposition that renders the question meaningful. This does not mean the presupposition is true or false. Also, note in this case the presupposition is not of the unprovable variety. In fact, the truth of the presupposition is potentially testable by empirical investigation. 

Above I mentioned that some treat a presupposition as an axiom. Unfortunately, that view was espoused by Gordon H. Clark in his version of presuppositionalism.  I agree with Van Til and Greg Bahnsen that Gordon H. Clark's version of presuppositionalism is fatally flawed¹.  His defense of Christian theism had to ultimately rest on the "axiom of Scripture." This essentially reduced Clark's system to fideism. As Bahnsen summarized: "Clark ultimately left Christianity without a rational defense."²      Clark's system leaned heavily to rationalism and deductive proofs when it came to the positive defense of Christianity. He was vehemently opposed to empirical evidence -- deeming it not a path to any knowledge. So much so that he claimed that science has no cognitive content regarding nature.  Only deductivism provided knowledge. These faults are serious, and actually are self destructive of Clark's system.³   One should be aware of the difference between Van Til's and Clark's  versions of presuppositionalism and not confuse the two.

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1 See Chapter 8.5, p.662 in "Van Til's Apologetic" by Greg Bahnsen for the critiques of Gordon H. Clark.^↩
2 p.672 in "Van Til's Apologetic" by Greg Bahnsen.^↩
3  N.B. Clark's writings are not devoid of value. His history of philosophy "Thales to Dewey" is an excellent text that thoroughly dismantles atheistic thought as being contradictory in all of its historical systems.^↩ 

More Nagelisms

I was perusing blogs awhile back (actually a few years!) when I came upon this quote from Nagel's Mind and Cosmos. Rather than consulting my notes it is just easier to re-quote it here.

First, that the non-teleological and timeless laws of physics--those governing the ultimate elements of the physical universe, whatever they are--are not fully deterministic. Given the physical state of the universe at any moment, the laws of physics would have to leave open a range of alternative successor states, presumably with a probability distribution over them. Second, among those possible futures there will be some that are more eligible than others as possible steps on the way to the formation of more complex systems, and ultimately of the kinds of replicating systems characteristic of life. The existence of teleology requires that successor states in this subset have a significantly higher probability than is entailed by the laws of physics alone--simply because they are on the path toward a certain outcome. Teleological laws would assign higher probability to steps on paths in state space that have a higher "velocity" toward certain outcomes. They would be laws of the self-organization of matter, essentially--or of whatever is more basic than matter. (pp. 92-3)

This is a good summary of Nagel's attempts to reintroduce teleology into the natural universe. Nagel realizes that neo-Darwinism is a fatally flawed theory. The gist of the argument is that naturalism has to reintroduce final causes. Blind chance and mechanistic evolution don't get it. Mixed up in the argument is the typical atheist reliance on chance and probability. The motions of matter are not deterministic.

Okay, for the sake of argument, let's grant that. As theists we deny that the source of "probability" is what the atheist claims it to be -- an ultimate irrational residue of lawlessness. A world in which things happen for "no reason!" But back to the technical issues.

The probability distributions of quantum field theory can be computed with some very precise results for things like scattering amplitudes,half-lives, branching ratios and the like. These probability "amplitudes" are all functions of the basic properties of the physical systems being modeled. And, here's the point: the amplitudes have no teleological aspect. All of physics exhibits non-teleology. The future state(s) of the universe are solely determined by the present state, past and future are irrelevant. This principle falls out rather neatly from the principle of least action -- a very general principle from which all equations of motion can be derived given a Hamiltonian (think, "energy") or Lagrangian function that depends on the constituents of the system and their configurations. Moreover Nagel's plan is to require "... that successor states in this subset [those favoring replicating life] have a significantly higher probability than is entailed by the laws of physics alone--simply because they are on the path toward a certain outcome."

The nail in this coffin is that Nagel imagines some non-physical laws that must alter half-lives, branching ratios and so on, along the way.  After all, according to the atheist myth of macro evolution, the journey to replicating life is via small steps with compounded probabilities. We ought to be able to see such evidence in pre-biotic chemical reactions.  

Embracing such non-physical laws is to accept a new dualism and to abandon the pillar of monism in the atheist's philosophy. Paradoxically, the positing of extra-physical (should we say supernatural!) properties seems not to worry Nagel's new born "naturalism." 

An Agnostic asserts: "Humans are not random objects like asteroids." I ask, " Are you sure?"

It has been awhile. Off busy with other activities. I had typically tried to write longer entries. The following short commentary is due to a comment found on social media a couple of years ago by an avowed agnostic who stated:

"Humans can and do agree amongst themselves what constitutes acceptable behaviour for the greater good of all. That's what distinguishes us from random objects like asteroids. Individual bad people including tyrants may depart from those standards just as they may break other human laws such as relating to fraud or democratic procedures."

This assertion, typical of evolutionary atheists and agnostics, was made in the context of the issue of morality. This person was arguing for conventional morals. But, of course, conventional morals are not true morals. Conventions are arbitrary and not absolute. This is moral relativism all in all. Different strokes for different folks.

But the main point is that, in this quote, we have yet another case of the unbeliever's contradictory presuppositions of his rational freedom and freedom from the causal matrix of quantum field theory in a reality of material monism. He claims humans are not "random objects!" Is he sure? Can he prove this assertion is consistent with his metaphysical presuppositions?

He can't. It is a mere assertion and contradictory to material monism. As a bundle of material he is just a configuration of quantum fields and, ipso facto, "a random object!" On his presuppositions he actually is no different than asteroids, or any other material object in the universe. He would be nothing but a clump of matter responding to the equal and opposite reactions from other clumps of matter in the rest of the universe. The same actions and reactions that have been going on for eternity in his mythology. And, of course, none of these actions and reactions are evil, and none are good.