The title is a quote from a Calvin and Hobbes strip. I read it as a kid, and I've found many, many situations in which it applies.
Today, for instance. I'm skimming through books on basic computer programming for teens, trying to find some suitable additions for the school library. In one of them, I run across the following discussion of inclusive vs. exclusive "OR" in Boolean logic:
Legal documents are supposed to be unambiguous. So this confusion between inclusive and exclusive or must be avoided. Thus legal documents often use one of these constructions: "p and/or q" (meaning inclusive-or, so it is possible that both are true), or "p or q but not both" (meaning exclusive-or)
Fun fact: I once went to law school. I graduated. I passed the bar exam (actually, two of them, in two separate states). I practiced law briefly, until the Great Recession kneecapped civil service. Then I went into a combination of college teaching and freelance writing. I also went back to graduate school.
Legal writing taught me the value of "and/or" to reduce the ambiguity of "or," the English word. So in grad school, I used "and/or" a LOT. I used "and/or" everywhere that I intended "inclusive or," and I used "either...or" everywhere that I intended "exclusive or."
Humanities professors uniformly LOATHED this. I cannot count the number of times I got dinged for it. One particularly crabby English professor circled every instance of "and/or" in a paper I submitted and knocked off one point for each of them. (The paper was on gender fluidity in the Roman de Silence - a 13th century story about a girl raised as a boy so her parents have someone to leave all their stuff to - so there was a LOT of "inclusive or" going on in that paper.) (I also think said professor chose that hill to die on in part because they couldn't fault my reasoning even though they hated its conclusions.)
Lawyers NEED to distinguish between inclusive and exclusive "or." So do programmers. By the time I got to grad school, I assumed that everyone embraced the value of distinguishing between the ors. It was jarring to me, then, to encounter professors - particularly professors *of English* - who refused to let me clarify that distinction in just four added characters.
I kept doing it, by the way. I hated how unclear arguments got when I left certain "ors" up to the interpretation of the reader. I also hated having to explain to people they were misinterpreting me. It was a lose-lose situation: I always felt I was implying that they were either (a) deliberately misinterpreting (if they knew they were misunderstanding me) or (b) stupid (if they didn't).
I have always been good at words. I have also always loved the clarity of Boolean logic. I don't find those contradictory. I think ordinary language use *has to* be inexact and messy sometimes. Humans are inexact, messy beings. If we were computers, we would not *need* computers.
But sometimes, when an expression makes communication clearer with no downside cost, it's silly to refuse it. I said what I said.
ADDITION a few hours later: Here's an example of what I mean when I say humans are inexact, messy beings who need our language to be messy and inexact sometimes too.
In the section of another book on well-formed functions, a quiz asks if the following counts as a wff:
(p ^ q) ^ ~(p ^ q)
My brain read this in English: "(p and q) and not(p and q)," and then said "I don't know how that's possible." I do, though. "Two things can be true at the same time even though they are partly or wholly contradictory and shouldn't be able to occupy the same space simultaneously" is a VERY common experience when dealing with grief.
From grief, lots of things are contradictory yet both true. I miss my husband, AND my life since his death is generally a good one. I love him deeply AND I love the life I've built since him. Those feel like they should conflict, but they exist in the same space.
Or: We need logic expressions for clarity. We need messy expressions because we are human. Both are true, and both exist in the same space. We contain multitudes.
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