To continue our series in valid forms of argument...
II. Modus Tollens (Latin, lit. “The mode of taking”):
A. Formally stated:
1. If P is the case, the Q is also the case;
2. Not-Q,
3. Therefore, not-P
B. 1. Illustrated from ethics:
(Here I cite Gregory Koukl and Francis Beckwith’s Relativism: Feet Firmly Planted in Mid-Air, 1999, 65.)
“In like fashion [to B. F. Skinner’s conclusions in Beyond Freedom and Dignity], relativists must remove the words praise and blame from their vocabularies. But if the notions of praise and blame are valid, then relativism must be false.”
The line of reasoning is modus tollens.
i. If (P) moral relativism is the case, then (Q) the words praise and blame are unintelligible.
ii. But, (not-Q) the words praise and blame are valid moral categories (even presupposed by relativists!).
iii. Therefore, (not-P) relativism is not the case.
B. 2. Illustrated from Scripture (1 John 2:19, speaking of the antichrist heretics):
“They went out from us, but they were not of us; for if they had been of us, they would have continued with us. But they went out, that it might become plain that they all are not of us.”
Again, modus tollens.
i. If (P) they had been of us, then (Q) they would have continued with us.
ii. But (not-Q) they did not continue with us.
iii. Therefore, (not-P) they were not of us.
B. 3. Illustrated from Sir Arthur Conan Doyle’s Sherlock Holmes, “The Adventure of Silver Blaze” (since Sherlock Holmes is Beaner new favorite movie!):
“A dog was kept in the stalls, and yet, though someone had been in and fetched out a horse, the dog had not barked. Obviously the visitor was someone whom the dog knew well...”
i. If (P) the horse thief was a stranger, then (Q) the dog would have barked, since the dog always barks at strangers.
ii. But (not-Q) the dog never barked.
iii. Therefore, (not-P) the horse thief was not a stranger.
C. The fallacy factor:
As with the modus ponens, discussed in pt. I of the Right Reasoning series, the modus tollens is susceptible to a formal logical fallacy, namely the fallacy of 'denying the antecedent.' (Remember, in the case of an “If...then” conditional statement, the “If” clause is the antecedent, and the “then” clause is the consequent.)
Obviously, the fallacious attempt at a modus tollens would formally follow like this:
1. If P, then Q;
2. Not-P,
3. Therefore, not-Q.
However, the conclusion, though perhaps true, doesn’t follow from the premises. This too is an invalid line of inference.
Consider this.
1. If (P) the doctrine of the perseverance of the saints (i.e., that the elect will persevere in their faith to the end) is true, then (Q) no Christian would denounce the faith.
2. However, (not-Q) some once-professed Christians do denounce the faith.
3. Therefore, (not-P) the doctrine of the perseverance of the saints is not true.
It is amazing how many Arminians believe this to be a reasonable argument!
D. This last argument is valid, yet unsound: (see section D of Right Reasoning, pt I).
Showing posts with label Koukl. Show all posts
Showing posts with label Koukl. Show all posts
Friday, January 29, 2010
Monday, January 18, 2010
GRASPING PRESUPPOSITIONALISM
Here is a helpful article from Gregory Koukl at "Stand to Reason." The focus of the article is on what’s called the problem of “moral grounding.”
Koukl begins with the classic objection to the faith, the problem of evil. He then uses the problem of moral grounding to indirectly defuse the challenge by pointing out that for the problem of evil to be real, evil must be real and so a violation of a real good. He then states the obvious, that relativists can’t raise the objection from evil honestly, since real and objective evil can’t exist in a relativistic framework.
At this point, Koukl presents a question.
“The grounding question is: Given that there is real evil and good, as well, why is the world the way it is? What properly accounts for this moral feature of the world?”
Granted, Koukl is a rationalist, epistemologically speaking. However, even a green-winged presuppositionalist will recognize the transcendental nature of the question Koukl sets forth. He goes on to argue that morality is deontological; that is, morals have an obligatory nature. Morals are not descriptive but prescriptive; they don’t tell us how things are but how they ought to be. Morals have an ought-ness about them.
Finally, Koukl demonstrates that obligation assumes personality. Obligation is something that exists between persons. Although I need to prune my Azaleas for spring, I don’t feel any obligation to them to do it for them. They are impersonal entities and impersonals don’t prescribe what persons ought to do. Morals therefore could only have their “grounding” in a personal moral-maker to whom we are obligated.
Koukl is quite apt with illustrations, and doesn’t let us down in this article. The illustration serves to show the a priority of morality, thus concluding that morals have their “grounding” in the personal, moral-maker God of Christian theism.
While this is a good article, I’m not commending it for what it’s worth in and of itself. I’d have you read the article and then consider the auxiliary application I’m going to suggest.
Yesterday I posted Robert Reymond’s attempt at defining the presuppositional apologetic method. Today I thought I’d use Koukl’s article as a springboard to helping those unacquainted with presuppositionalism grasp it better.
Christians who are the slightest bit self-conscious in their apologetic practice are generally accustom to denying unbelievers any grounding for morality, since only Yahweh, the holy Law-Giver, alone has the authority to tell us what is right and wrong. This is nothing especially new; Koukl is sort of playing Capt. Obvious in this way.
A helpful step in grasping what distinguishes presuppositionalism from traditional methods is that the presuppositional apologete extends this denial of “grounding” from the unbeliever to every sphere of human experience, especially the area of epistemology.
Epistemology is the study of how we know what we know, the methods and extent of our knowing, et cetera. My favorite definition is (roughly stated) “When asked how you know what you know, then take away the option of answering, ‘I just do,’ and what is left is epistemology.”
The presuppositional challenge to unbelief is that unless the God of Christian theism is presupposed at the beginning, knowledge of anything is impossible. Christ, the Word of God, endowing light and speaking with absolute and Self-attesting authority alone provides the necessary “grounding” for the integration and unity of knowledge necessary for human knowledge to happen at all. It is an epistemological axiom that unless everything is known by Someone, nothing can be known by anyone. Exhaustive knowledge must reside Somewhere in order for any knowledge to reside elsewhere. (I capitalize “Someone” and “Somewhere” in the preceding sentences because in Whomever or Wherever all knowledge resides, that one or place deserves this respect!)
The traditional apologetic method Evangelicals are so used to ironically operates on a Roman Catholic understanding of anthropology and the fall of man. The traditional apologetic operates on the assumption that the fall had little or no effect on man’s reasoning ability; sin is a moral rather than epistemological issue, or so it’s presumed. This, however, cannot stand against either the biblical data, human experience, or historic Protestant theology. That the fall was primarily an epistemological laps is sufficient to prove the Romish doctrine wrong.
Tomorrow I’ll post what I believe is a positive vindication of these claims. In the mean time, ponder this analogy. Presuppositionalism is (in part) just an extension of Koukl’s argument in his “moral grounding” article. Presuppositionalism argues that God speaking in the Word of God is the transcendentally necessary ontological “grounding” for knowledge. We argue that human reason, the laws of logic, induction, et cetera depend upon humans being created in God’s image; the biblical God, who is the comprehensively rational One. Moreover, since the all the world reflects his glory, majesty and “eternal power and Godhead,” the world has a rational structure which corresponds with not only God’s Mind, but man’s as well. Therefore, God is the necessary ontological “grounding” of epistemology, from the impossibility of all contrary epistemological options.
This illustration, from the moral argument to the epistemological argument, may help some grasp the distinctives of a presuppositional apologetic.
Koukl begins with the classic objection to the faith, the problem of evil. He then uses the problem of moral grounding to indirectly defuse the challenge by pointing out that for the problem of evil to be real, evil must be real and so a violation of a real good. He then states the obvious, that relativists can’t raise the objection from evil honestly, since real and objective evil can’t exist in a relativistic framework.
At this point, Koukl presents a question.
“The grounding question is: Given that there is real evil and good, as well, why is the world the way it is? What properly accounts for this moral feature of the world?”
Granted, Koukl is a rationalist, epistemologically speaking. However, even a green-winged presuppositionalist will recognize the transcendental nature of the question Koukl sets forth. He goes on to argue that morality is deontological; that is, morals have an obligatory nature. Morals are not descriptive but prescriptive; they don’t tell us how things are but how they ought to be. Morals have an ought-ness about them.
Finally, Koukl demonstrates that obligation assumes personality. Obligation is something that exists between persons. Although I need to prune my Azaleas for spring, I don’t feel any obligation to them to do it for them. They are impersonal entities and impersonals don’t prescribe what persons ought to do. Morals therefore could only have their “grounding” in a personal moral-maker to whom we are obligated.
Koukl is quite apt with illustrations, and doesn’t let us down in this article. The illustration serves to show the a priority of morality, thus concluding that morals have their “grounding” in the personal, moral-maker God of Christian theism.
While this is a good article, I’m not commending it for what it’s worth in and of itself. I’d have you read the article and then consider the auxiliary application I’m going to suggest.
Yesterday I posted Robert Reymond’s attempt at defining the presuppositional apologetic method. Today I thought I’d use Koukl’s article as a springboard to helping those unacquainted with presuppositionalism grasp it better.
Christians who are the slightest bit self-conscious in their apologetic practice are generally accustom to denying unbelievers any grounding for morality, since only Yahweh, the holy Law-Giver, alone has the authority to tell us what is right and wrong. This is nothing especially new; Koukl is sort of playing Capt. Obvious in this way.
A helpful step in grasping what distinguishes presuppositionalism from traditional methods is that the presuppositional apologete extends this denial of “grounding” from the unbeliever to every sphere of human experience, especially the area of epistemology.
Epistemology is the study of how we know what we know, the methods and extent of our knowing, et cetera. My favorite definition is (roughly stated) “When asked how you know what you know, then take away the option of answering, ‘I just do,’ and what is left is epistemology.”
The presuppositional challenge to unbelief is that unless the God of Christian theism is presupposed at the beginning, knowledge of anything is impossible. Christ, the Word of God, endowing light and speaking with absolute and Self-attesting authority alone provides the necessary “grounding” for the integration and unity of knowledge necessary for human knowledge to happen at all. It is an epistemological axiom that unless everything is known by Someone, nothing can be known by anyone. Exhaustive knowledge must reside Somewhere in order for any knowledge to reside elsewhere. (I capitalize “Someone” and “Somewhere” in the preceding sentences because in Whomever or Wherever all knowledge resides, that one or place deserves this respect!)
The traditional apologetic method Evangelicals are so used to ironically operates on a Roman Catholic understanding of anthropology and the fall of man. The traditional apologetic operates on the assumption that the fall had little or no effect on man’s reasoning ability; sin is a moral rather than epistemological issue, or so it’s presumed. This, however, cannot stand against either the biblical data, human experience, or historic Protestant theology. That the fall was primarily an epistemological laps is sufficient to prove the Romish doctrine wrong.
Tomorrow I’ll post what I believe is a positive vindication of these claims. In the mean time, ponder this analogy. Presuppositionalism is (in part) just an extension of Koukl’s argument in his “moral grounding” article. Presuppositionalism argues that God speaking in the Word of God is the transcendentally necessary ontological “grounding” for knowledge. We argue that human reason, the laws of logic, induction, et cetera depend upon humans being created in God’s image; the biblical God, who is the comprehensively rational One. Moreover, since the all the world reflects his glory, majesty and “eternal power and Godhead,” the world has a rational structure which corresponds with not only God’s Mind, but man’s as well. Therefore, God is the necessary ontological “grounding” of epistemology, from the impossibility of all contrary epistemological options.
This illustration, from the moral argument to the epistemological argument, may help some grasp the distinctives of a presuppositional apologetic.
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