Daily Archives: June 27, 2017

Re: Nonsense and Self-reports

Mr. Nance,

I am using your Introductory Logic course to teach an informal class in logic to four young people in my church. Thank you for creating a rigorous, explicitly-Christian logic textbook!

During a recent class (working through Lessons 6-8), two questions came up. Can I get your thoughts on them?

(1) Nonsense Statements

On page 57 you give the example of the nonsense sentence “The round square sweetly kicked the green yesterday.” A few students began waxing philosophical about what precisely rendered this sentence nonsense. One asked if it was nonsense in virtue of the fact that squares, by definition, cannot be round. If so, they asked, wouldn’t the sentence, “The square sweetly kicked the green yesterday” be eligible for statement-hood? Sure, squares aren’t known to kick, but that only means that the sentence is likely a false statement. Further, “green” might refer metaphorically to the green grass or a public common grassy land.

I love having such inquisitive students, but I’m afraid I wasn’t able to give them a tidy answer to these questions: Instead, I suggested that we take statements like “this statement is false” as clear examples of nonsense and leave the rest for an epistemology class. What would you have said?

(2) Self-supporting statements

There was some consternation about the notion that self-supporting statements are true (p. 61). One student gave the example of James 2:14 where the self-report “I have faith” is false. I answered by saying that, in general, we should give self-reports the benefit of the doubt. That is, we should judge a self-report true, until or unless we have some good reasons or arguments for thinking it false. Of course, this doesn’t mean that all self-reports are true. Categorizing self-reports as self-supporting, I told them, is more a point of intellectual decency and doing-as-you-would-be-done by than of hard logical categories.

I also pointed out that many self-reports fall into the category of incorrigible statements—that is, for some self-reports, we simply will never have any means, whether by authority, experience, or deduction, of proving them false. Most self-reports about mental states fall into this category—for example, “I wish I had purchased Apple Stock five years ago.”

If you can give any general pointers here, I would be grateful. Thank you. Continue reading Re: Nonsense and Self-reports

Christian Logic

I was recently asked the question, is there a distinctly Christian view of logic? I offer here the beginning of an answer to that question. (I am not trying to be original here. These thoughts are from many sources. Just trying to be faithful.)

Laws of Logic

The laws of logic are universal (applicable everywhere), abstract (immaterial, grasped by thought), invariant (not changing), and authoritative (they must be accepted). A non-Christian worldview has a difficult time accounting for such laws. The laws of logic cannot be denied with any kind of consistency, since a denial of logic is tantamount to a denial of truth and reason. But if it is affirmed that the laws of logic are universal, abstract, invariant, and authoritative, yet not “from God,” how can they be justified? Where do such laws come from? They are not invented by men, because they would not then be universal, invariant, or authoritative. They are not material, because they would not then be abstract.

Rather, logic is an expression of God’s unchanging, orderly, truthful, authoritative character.

The Character of God

God Himself is logical; He is a reasoning being: “Come, let us reason together” (Isa. 1:18).  As the ultimate lawgiver He orders His cosmos in a logical way. “God is not a God of disorder” (1 Cor. 14:33). God is orderly, and order implies reason. Where there is no reason, there is only chaos. God’s word is truth (Jn. 17:17), and He would have us be truth tellers (Eph. 4:15). God Himself is non-contradictory. He is truthful (Jn. 3:33), He cannot lie (Heb. 6:18). He does not deny Himself (2 Tim. 2:13). John Frame, in his book The Doctrine of the Knowledge of God, identifies these attributes of God, and then adds: “Does God, then, observe the law of noncontradiction? Not in the sense that the law is somehow higher than God Himself. Rather, God is Himself noncontradictory and is therefore Himself the criterion of logical consistency and implication. Logic is an attribute of God, as are justice, mercy, wisdom, and knowledge.”

The Christian worldview does account for the properties of logical laws. The laws are universal because God is omnipresent; His character is expressed throughout His creation. The laws are abstract, needing no created, material foundation, because they existed before the creation, being attributes within God. The laws are invariant, because God does not change, and neither do His attributes. If the laws of what is true and rational could change, then how could God be trustworthy? How could He keep His covenant promises if truth could be non-truth? He can and does keep His promises, because Christ, the logos, is the same yesterday, today, and forever. The laws are authoritative, because God is the ultimate authority.

A Tool and Gift

God has communicated logic to man as a tool by which we can come to truth. God made us in His image with the ability to reason. We are created as rational beings, and God uses our reasoning ability to speak to us. For example, the giving of law presupposes an ability to reason. Laws are given in the form of universal propositions. “God has commanded all men everywhere to repent.” To obey this, we finish the syllogism: I am a man, therefore I must repent. Without logic, the command could not be applied to particulars. A denial of logic opens the door for disobedience, for without it we cannot obey.

Logic is presupposed, not only in law, but in all revelations of God to men. God gives us minds that reason just as He has given us eyes that see, in order that we may receive His revelation to us. Cornelius Van Til said, “The gift of logical reason was given by God to man in order that he might order the revelation of God for himself.” In order to comprehend any doctrine, we must use logic. The truth that there is one God, eternally existent in three Persons, though clearly contained in the Bible, is not found in any one place in scripture. To see the truth of the Trinity requires a godly, submissive use of logic. If a truth is truly and logically derived from the scripture, we have a divine obligation to believe whatever it is. This is what the Westminster Confession is referring to where it says, “The whole counsel of God concerning all things necessary for His own glory, man’s salvation, faith and life, is either expressly set down in scripture or by good and necessary consequence may be deduced from scripture.” Isaac Watts, the great hymn writer and logician, said it this way in his book on logic: “It was a saying among the ancients, Veritas in puteo, Truth lies in a well; and, to carry on this metaphor, we may very justly say, that logic does, as it were, supply us with steps whereby we may go down to reach the water…. The power of reasoning was given us by our Maker, for this very end, to pursue truth.”

Logic is thus a tool which God has given us in order to understand and obey Him. Like other tools, our grasp of it as humans is no doubt incomplete and imperfect, but it is sufficient for the task for which it is given. And like any other tool, we need to be careful how we use it.