If you work crossword puzzles, you get used to certain words that get used over and over because they combine well with the words that intersect with them. For instance, the word "ape." Now, there's nothing wrong with "ape" when you define it as "Chimp, e.g." or "Orang or Gibbon." Because those are nouns. And if you've got four letters, "apes" is also an easy word to fit in.
But I must confess that I'm weary of seeing lazy cruciverbal constructors who define "ape" as a verb -- "to imitate." I do remember, in my youth, now and then hearing somebody refer to one person "aping" the behavior of another. But that's the only way I heard it, as the gerund or participle "aping."
I'm now at least fifty years older than I was the last time I heard "ape" used as a verb in actual conversation. Crossword makers go even further, however, using variations that I have never seen or heard outside of crosswords: "Aped," the past tense, and the unimaginably awful "aper" -- someone who imitates other people.
I believe that word was never uttered by anyone, anywhere, in a naturally occurring conversation.
Raise your hand, if you've ever heard a person use one of those words in actual conversation. If you have, I promise you that the person who said it does crossword puzzles so often that they actually came to believe that there really is a verb "to ape" that can take all the affixes of any other verb.
But you can make a case for "ape" as a verb because it once was used. What can't be forgiven is a crossword puzzlewright who needs to fit "a priori" into the puzzle, and then defines it as "deductive."
Now, it's true that you are most likely to learn "a priori" in a class on logic, and it will show up when you're learning about deductive reasoning. But the meaning of "a priori" (pronounced AH-pree-OR-ee) is the opposite of "deductive."
Deductive reasoning is where you start with certain premises, like "all humans are bilaterally symmetrical bipeds" and "Greeks are human." From these two premises, you can deduce "All Greeks are bilaterally symmetrical bipeds."
(You can't deduce that all bilaterally symmetrical bipeds are human because, you know, the entire bird class [as if they all went to school and graduated together] consists of bilaterally symmetrical bipeds.)
Here's the thing. Deductive reasoning can lead you to the conclusion of a syllogism, which is great as far as it goes. But the two premises, "all humans are bilaterally symmetrical bipeds" and "Greeks are humans" are not deductive. They are assumed to be true for the purpose of checking the syllogism, but they themselves are not proven in or by the deductive process.
The premises are considered to be "a priori" knowledge, rather like some character in Game of Thrones saying "It is known" as their authority for some outrageous statement.
In other words, a priori statements are by definition not deductive, not demonstrated, but are merely presumed to be true for the purpose of the syllogism.
This is why logic can't actually prove anything, all it can do is disprove something by demonstrating that it is absurd or illogical. For instance, if your political bent is to say, "All Republicans approve of Donald Trump" and "All people who approve of Donald Trump are cretins," then within that syllogism it is perfectly logical to conclude, "All Republicans are cretins."
The logic is sound; but the a priori premises are demonstrably false. First, you might have a hard time proving that all Republicans approve of Donald Trump (come on, we know that many Republicans loathe him); and second, you'd have an even harder time proving the cretinhood of Donald Trump's supporters, who include many very smart and well-educated people, along with at least the normal number of cretins that follow any political leader.
So deductive reasoning can be completely valid (i.e., correctly stated and derived) while being ridiculously false because the assumptions -- the a priori statements -- are absurd. People who don't know to question the premises of a deductive argument are at a loss when someone hits them with an idiotic syllogism like that one.
To all those who create crossword puzzles: Please stop using a definition just because other cruciverbalists have used it. Everyone who uses "deductive" as a definition for "a priori" is not just wrong, but humiliatingly wrong.
What makes me really sad, though, is that nowadays our lexicographers record even bad misuses of a word, and I can imagine a day when our dictionaries will include "deductive" as a legitimate meaning of "a priori." That sort of thing happens all the time these days. There's no stemming the tide of ignorance. People who don't take pains with the English language eventually prevail.
You heard about it here; you see the examples in crossword puzzles; and when the puzzlewrights scream that I'm wrong, it's in the dictionary that way, I will smile sadly but benignly and then wink at the rest of you to say, "They have just demonstrated my point."
on the art and business of science fiction writing.
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