Subalternation (done wrong) commits the existential fallacy when the terms are empty (the premises aren’t true), because existential import (at at least one time, t, which has essential/thetic import now if that time, t, is not now) is required (empty terms are forbidden, true universals/superalterns are required) in order for subalternation (not to mention affirmation) to “go through”.
A universal claim like All A are B has to be considered true. The reason being, if not, since the particular claim Some A are not B is false if the class A is empty, we lose the contradictoriness of the universal affirmative (All A are B) vs. its particular negative (Some S are not B).
If the subject class/term (A) for a universal affirmative (All A are B) is not empty, the inference subalternation is valid.
particular affirmatives (Some A are B) and particular negatives (Some A are not B) have existential import.
Are there other ways that these 4 categorical statements “hang together”? Je ne sais pas.
You can’t pull out a true particular when you start from an empty universal. Even if the particular is the only member in its class, it isn’t empty, is it? Why is this even an issue?
The syllogistic fallacy of exclusive premises (two negatives), due to not being able to deduce ex nihilo (affirmative conclusion from negative premise), should also require existential import (although I think we need to upgrade to three kinds of import: ontic, deontic, and thetic import - Defining the Imports) of all terms, including universals—should consider a premise with an empty term/category to be unsound (that would mean the REAL existential fallacy is a premise that is unsound or falsely (due to lacking import) presumed sound, rather than the requirement of import itself being fallacious). See Wilford Hodges” book, Logic, pages 132 to 134, regarding designators requiring a purely referential occurrence, a primary reference. This is basically the same thing as existential import.
An author thinks Aristotle views subalternation as a form of weakening - doesn’t say why. BUT, author also thinks Aristotle views darapti (in the third figure) as strengthening the minor premise in datisi.
Difference between darapti (in the third figure—the middle term on the left in both premises) and datisi:
Darapti in the third figure:
If all black swans are black
and all black swans are swans
then some swans are black
Datisi:
If all black swans are black
and some black swans are swans
then some swans are black
The author disagrees datisi is weaker than darapti, because the apparent strength of the “all” in darapti’s minor premise … DROPS ANY MENTION OF EXISTENCE … which to the author means it relies on its conclusion being sound (relies on the truth of the conclusion)—in other words… it has a sort of circularity where the premises are only true if the conclusion is true.
The author has this bias: They think you go from example to universal…rather than examples demonstrating (nonempty) universals.
Things/claims are either true or not. It doesn’t matter what you “assign” them in terms of a ‘truth value’. There is a clear difference between talking about something and only talking about how we talk about it; the former is philosophy, the latter… mere intellectualism.
They probably have a delusive bias if they expect a statement to be true that doesn’t, hasn’t ever, will never, and/or cannot possibly ever, describe anything in reality.
Like I said above, responding to the charge of circularity, the fallacy of exclusive premises is based on the fact that you can’t pick out a particular from an emptiness. Why are we going to accept that reasoning, but we’re going to allow for empty universals? We’re not! How ironic that the author starts with false premises and then says the expectation of true premises (existential import…aka soundness) is only possible (& therefor circular) if the conclusion is true. He applies the expectation of existential import REGARDLESS of a lack of import—which would necessitate discarding the premise. You CANNOT make that make sense.
Side-note before I forget: If we’re going to dismiss the existence of numbers like one, we have to dismiss the existence of words like or. There is an exclusive one (particularity, singularity — not the same thing) and there is an inclusive one (whole—doesn’t rule out iteration).
That sidenote is relevant to how I said we need to have three different imports to allow for the fact that something may not yet be true or something may have been true previously and we just didn’t know it. And stuff like that… like the meaning of numbers and distinctions… etc.
Etc. etc. etc.
It’s not like I know, learned, or remember everything. So, please, if I’m making a fool of myself, and you pride yourself in seeing the lightbulb come on for someone who you may have written off for whatever reason… don’t give up trying to explain why you think you/somebody besides myself… are/is right about this, versus my position. I do enjoy learning I was wrong, and new ways of seeing things. As long as they’re real.
I guess this is a good time to suggest reading Aristotle’s take on the issue. From what I could gather he was aware of the existential fallacy mentioned in the OP.
define existential, spirit, geist/understanding universal placement, self evidence/importance/relevance, you have to start from the ground up as in zen or daoism
