Justification of a priori beliefs

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Puritan Board Sophomore
A standard move within christian apologetics is to ask the scientifically-minded atheist what reason he has for believing that his sense are reliable, that the world has the same logical structure as his mind, that memory is reliable etc.

The christian would answer that as we presuppose that God has created us for knowing Him and His creation we have an adequate ground for believing in the reliability of our cognitive faculties.

But cannot the atheist in a similar manner reply that he presupposes that evolutionary forces have given him reliable cognitive faculties? In that way the force of the christian argument is removed.


Puritan Board Senior
I would argue that evolution itself presupposes order. The atheist would have to defend their belief in "order" before they could ever come to the idea of animals being able to be considered in ordered groups...and certainly before they could come to the idea of an ordered evolutionary concept.

Since many adhere to the Big-Bang theory of creation, the main thrust of my argument would be to show them that using the scientific method we can't show that order comes from chaos....in other words, an explosion can't create an ordered universe that would defend their concept of evolution.


Puritan Board Freshman
It seems to me that something is gained just by getting them to admit that they have presuppositions. Their usual argument is that their beliefs are based on logic and reason, rather than faith. But a presupposition is by definition not established by logic or reason. They exercise faith in their starting point as much as we do. Then the question becomes, why put your faith in that, rather than God? That ultimately is a choice of the heart.


Puritan Board Graduate
The argument that you laid out is sadly the one most people lay out and its simplicity betrays its real value. The actual developed argument is much more complex. With that said a slightly more complex argument would be this.

In the philosophy of science there is a constant logical problem that no seculer philosopher has ever been able to overcome the problem of induction. The problem is basically this how do I know that the next time I preform an experiement the laws of nature will be the same as the last time I preformed the experiement? This question reveals two faithbased assumptions of science:
1. The uniformity of nature. This means that nature behaves in a uniform manner, or basically the same all the time and everywhere.
2. That the laws of nature for the most part stay the same over time.

Now these two assumptions are faithbased meaning that I trust on some rational grounds that these two assumptions are correct. For instance how do you know that the laws of nature won't miracusly change in the next few seconds? You have faith in the above two assumptions which would gurantee that they won't. Most scientists just make these assumptions and go about there buissness, so if they chide you for having faith in Christ chide them (with the above argument) in their faith in science. Now this is a logical problem whether or not you deal with it or not.

Most people may have an explination handy or not but when we are dealing different philosophies or worldviews we can gain a general explination or reasons for a person's faith in science. Lets take a basic atheistic-materialist view and set it over against the christian view. I have been following the atheist's hope for some time now that a Darwinian philosophy will replace God as an explination for regularity in natural laws, like they claim it did for biology. But lets examine their claims. I think there are several inconsistancies in their argument.
1. If the laws of the universe evolved from previous states of affairs than they have no guarentee that these same laws will not keep evolving into new states of affairs. Thus they have no rational ground on which to have faith in the two assumptions mentioned.
2. Darwinian laws of eviolution as applied to natural laws become problimatic because these same laws must be material in nature, the materialist angle of the atheism under discussion, so did they evolve too? Or can they evolve? If they can't than these are a type of natural law that doesn't evolve, or had to always be static, and now requires an explination on how they got there. This ambuigity is no rational basis for their faith in the two assumptions, because those metaphysical laws of the laws of nature must be explianed on an evolutionary basis and then the laws about those laws must be explinaid and on and on into infinity.

The christian on the other hand beleives in a creator who holds and sustains the universe in constant motion and regularity. It is in this belief that we have proper rational grounds to have faith in the two assumptions mentioned above. So over and against the atheist-materialist they have no rational grounds for having faith in the two assumptions but we do. There are other minor types of atheism out there that we would have to tailor our arguments for but this by far the majority view in our western culture.


Puritanboard Amanuensis
But cannot the atheist in a similar manner reply that he presupposes that evolutionary forces have given him reliable cognitive faculties? In that way the force of the christian argument is removed.

Yes; so his presupposition is based upon the chance event of evolution and contains no moral or personal value.


Puritan Board Doctor
Evolutionary argument against naturalism - Wikipedia, the free encyclopedia

Plantinga's evolutionary argument against naturalism is also suggestive in this regard.

Basically atheists are asking us to take seriously the electrical impulses that deterministically travel through their meaty brains, which according to them have arisen in an impersonal, irrational universe that is governed by chance and fate.

The above paragraph could be expanded in much greater detail to spell out the reductio ad absurdum.

Atheists are asking us to take them seriously as walking, talking accidents in an accidental universe.


Puritan Board Freshman
Well first, not all presuppositions are a priori, as someone presupposing an evolutionary framework would only have come after a great deal of "education" and self-deception. But a priori beliefs are justified (or more accurately, false a priori beliefs are proven unjustified) usually by reductio ad absurdum type arguments. Do they rationally and accurately provide an account of and justify the reality in which we find ourselves? Claiming that you can justifiably presuppose that an evolutionary process led to our rational faculties actually subverts its on conclusion (i.e., that we have anything like what philosophers have historically called "rationality"). Alvin Plantiga rightly shows that evolution would not yield TRUE ideas, but merely USEFUL ones (which often are false), and hence, our belief in evolution itself cannot ever be shown to be TRUE, but only USEFUL to our evolutionary progression. So even without looking at the ultimate conclusions about reality that an evolutionary presupposition would yield, the presupposition itself proves itself utterly unreliable by its very structure.
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