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.
It sounds like you have some excellent students. As a teacher, I always appreciate young people who will ask questions that demonstrate their desire to truly learn the lessons being presented. So let me see if I can offer some responses.
(1) Great question about what *really* makes that example nonsense. To be sure, the word “round” was added to guarantee that the given sentence was nonsense. I added “sweetly” because I could not imagine how something could be sweetly kicked (though upon reflection, I have nudged my wife under the table with my foot in a way that might be described as sweet). I was using “yesterday” as the direct object of the kick, and “green” as an adjective describing the yesterday. In that sense, a yesterday cannot be green nor be kicked. (Maybe it would have been clearer to say “The round square sweetly kicked the yellow tomorrow.”)
I was arguing that, for reasons like these, “the round square sweetly kicked the green yesterday” does not and cannot refer to anything, and so we can describe it as nonsense. If the words actually could refer to something that was just not the case, then it would be false. For example, “The tongues of flame at Pentecost were water” refers to something, so it can be a false statement.
I did this to try to give a different example of nonsense than “This sentence is false.” I also wanted to give an example of a nonsense sentence that used actual words, rather than one like “Kuto nyksed jihdlaq nonsadih.”
Your response is a reasonable one, and I think I have resorted to a similar answer with particular students before. I have also encouraged students to try to think of their own nonsense sentences that use actual English words and correct syntax.
(2) Your response to the question about self-reports was exactly what I was trying to communicate. It is largely a question of being polite, giving people the benefit of the doubt in describing their own thoughts or feelings.
In teaching about self-reports, I also was trying to show that statements like “I think X” can be true, even though X is false. This can be an important point of distinction in discussion or debate.
In regard to James 2:14, the claim “I have faith” is false in that context because the speaker intends it to mean “I have saving faith,” even though their faith results in no good works. James is arguing that faith that does not work is in fact not saving faith. So yes, it is possible to objectively judge some subjective self-reports. In such cases, they can be considered false.