Jeremy,
No I am not. I am explicitly accepting that. Squares and circles are abstract concepts defined within the framework of human reasoning. They are definitionally mutually exclusive. You may say some other reasoning framework exists somewhere in which squares and circles can be the same thing, but the objects to which you are referring are explicitly not the squares and circles of our logical framework.
But you’re saying here “if I define squares as having right angles then a shape without right angles cannot be a square”. That tells us nothing about the universal properties of squares and circles though – just about the definitions we (currently) apply to them. That doesn’t mean however that it’s impossible for a square also to be circle nonetheless because current definitions do not necessarily map to that potential reality.
Was it? I don't believe that is the case. I think people just thought of them as different phenomena. People don't usually define things in terms of what they are not.
Yes. “Things” were defined as one thing or a different thing, but it was thought to be impossible for them to behave as both at the same time.
I don't think the problem arose until people started observing objects that appeared to behave like particles in some circumstances and waves in others. The resolution was simple in that it turned out that quantum level objects are neither particles (in the Newtonian sense) nor waves but objects whose behaviour can be described by mathematics that looks identical to the mathematics of waves.
Yes, but the point rather is that something considered impossible wasn’t. I referenced the quantum not to have discussion about it, but rather to illustrate that sometimes things though to be impossible are later found to be not impossible – ie, we cannot rule out the possibility that anything else currently thought to be impossible isn’t impossible after all.
It is by definition because it is a definition.
But not necessarily the reality it seeks to define. That’s the point. We define “square” in a very specific way, but that’s all it is – a definition. Who’s to say that one day someone might not say, “unlike what we thought squares to be back in the 21st century, we now know that squares have all sorts of different circular properties too”?
But in our "celestial computer", 2+2=4 ids a fundamental truth. It may not be in some other celestial computer (seems unlikely though), but it is certainly true that "in our reality 2+2=4"
But what makes you think that
our reality is also
the reality, and in the game it’s not only a “fundamental truth” inasmuch as that’s what an algorithm tells “us” to think? Axioms are also referred to sometimes as assumptions – and for good reason: assumptions can be wrong.
On what basis then could we be sure that claims of impossibility that rest on axioms might not also therefore be wrong?
Wrong. Axioms do not have to be "true".
Yes they do if you want to rely on them to claim a consequent universal truth – ie, that something is universally impossible. As you cannot know an axiom to be universally true though, accordingly you cannot then assert the consequent claim of “impossible” to be a universal truth.
Mathematicians use them and invent them and see if interesting things come out in the wash. For example, if you take as your axioms the five geometric axioms of Euclid, you can show by a line of logical reasoning that the angles of a triangle always add up to two right angles. However, it turns out that you don't have to accept one of the axioms - the "parallel postulate". If you substitute it with a different axiom, you find that the angles of a triangle do not add up to two right angles. The statement "the angles of a triangle add up to 180 degrees" is false, but the statement "if we accept Euclid's axioms including the parallel postulate, then the angles of a triangle add up to 180 degrees" is true."
But that “if” is what undoes you here. It’s a conditional proposition, but what if the underpinning axioms for it are wrong? All that you’ve said here is true, but there’s an unspoken suffix: “according to current human understanding”. That’s the problem with claiming epistemic impossibility.
There really is no such thing as a square circle.
At a colloquial level that’s fine, but not necesriy at a universal level. How could you know that to be true?
Shakespeare got there before you by the way: “There are more things in heaven and earth, Horatio, than are dreamt of in your philosophy” (Hamlet)
There might be life after death, but I doubt it and I would bet my house that there isn't.
So would I, but still I can’t justifiably calling it categorically, universally, 0% chance of it being true
impossible. That’s the point here.