Woo! This thread got WAY more love than expected!
Naah, an ardent empiricist just met an ardent scepticist...
Okay, I'm a bit short on time right now, so I won't be able to do an in-depth reply. Just a couple of questions though:
-What would be a non-tautological formulation of your first axiom? (I'm afraid it's a bit... useless right now )
-I1 and I2 are mutually exclusive; which one do you pick? Or what other flavor? What implications does that have for your argumentation?
-How do you avoid my headache while still using something like I2?
-Is "the human mind" a subset of "stuff that exists"? How does "describability" differ from attributes like "red", "delicious" or "immutable"?
-In what cases is it not sufficient to identify objects (or "classes of objects", which I'd like to refer to as objects themselves, if we can agree on that terminology) with their observed parameters? If there are none, why do you need (the refined version of) the first axiom?
-About that Bayes bit: How do you determine P(W), P(S) and P(S|W)? In other words: How do you define probabilities? Laplace won't work in this context, I'm afraid...
- It is not tautological, although it may sound a bit tautological due to wording. But you know, written at 2AM and all. But allow me to rephrase: that which we perceive to exist, exists. Not to be confused with Berkeley's 'what exists is what we perceive exists'. Reality is not an illusion nor only a product of one's mind. Reality is separate from perception. See below.
- Both. In a rather weird way. It is I1, but I1 that appears to be I2, depending on what level you're looking at. We're in a perfect closed container. Let's take... hmm... a two-by-four. It's a piece of wood. Nothing special about it. Now let's set it on fire (with a tinderbox we also have). We now have a pile of ashes, some heat, and some gasses or particles suspended in the air. OMIGOSH, WOOD DISAPPERD, HALP!
It appears that one object transformed into another. But all the atoms and energies that constituted the items inside our containers are still there, just changing location. If you treat matter as a special form of energy, as it appears to be, even if we used a nuclear reactor instead of a piece of wood and a tinderbox, the result would be the same. The shapes change, but the objects that create the shape are unchanged.
But, humans don't live on the sub-atomic level, so we normally concern ourselves with macro-scale, and for the sake of computing, you might approximate (use a simplified model of) macro-scale items as objects themselves (as you might have noticed, I use 'item' for any 'thing' as understood in everyday language, e.g. a desk, a computer, but also an atom, and 'object' for the lowest-level possible item, something like what atoms where thought to be before sub-atomic structures were discovered. I guess that it might be a little misleading, 'atomos' could be a possible term to describe it, but for now it's 'object' vs. 'item'.).
So for the purposes of macro-scale computation, items are modelled as objects, and a good chunk, if not all, of attributes are macro-scale approximations objects' states within the structures of an item. Using the examples you've given, 'red' is an approximation of the range of wavelengths of lightwaves, and wavelengths of lightwaves themselves are an approximation of OH GOD QUANTUM PHYSICS IS WEEEEIRD.
'Delicious' is an approximation of the chemical reactions starting at chemicals in food binding with specific receptors, biochemical reactions happening during neurotransmission and processing, etc., which are in themselves a little more accurate models of energy and matter transfers that happen at sub- and interatomic levels, etc.
'Human mind' is both 'stuff that exists' and an approximation. On the purely material level, it's an incredibly complex web of synapses, neural and glial cells, structures, etc., and on the 'cognition' level it is an approximation of the processes going on between the things on the purely material level, and that in turn is a model of et caetera, et caetera.
'Describability' and 'Immutable' are both more difficult, because they are remarkably more abstract. The former is an approximation of the processing capabilities of minds that allow them to create and use a labelling system of sorts, that being a simplified model of certain biological 'circuitry', being a model of you know the drill.
I'm going to skip 'Immutable' unless you really press me for it, because I think both me and you are tired by re-iterating the same pattern of thought for each example. To sum up, I accidentally into Plato, or maybe moderate realism, in a way, although without separating the realms of the real and of the ideal - every concept we use in day to day life is a simplified model of the objects it is composed of at the most basic possible level.
As I've been writing the above, I've been tempted to use an IT metaphor. In an IT-world, an object is an 'on' bit (1). The 'off' bit is a state of not-on (you can flip the base object to 0 and 1 to not-0 freely, but a positive base is more appealing aesthetically).
Like objects in our world 'form' atoms (nothing about the objects themselves change, merely their configuration - where they are, and where they are not), bits 'form' various bytes, depending on where the objects are and where they aren't - where there are 0's and where 1's.
But now, let's zoom out a LOT. You've got a program - let's say forum code. It lets you post funny images, debate philosophy and download games about psychotic drunkard midgets. And now... Enchance. ENCHANCE. ENCHAAAAAAANCE. What do you see? You see a string of bits. It's still the exact same forum code it was before, and whether you perceive it as a string of bits, lines of readable code or an actual forum you can use, it remains one and the same item, composed of objects that remain the same ones and zeros they were before.
Similarly, our world's objects form structures that, despite being nothing more that sets of objects arranged into patterns, exhibit emergent behavior. Atoms bond. Humans formulate abstractions. Programs give you functionality you wouldn't otherwise have.
Holy shit, that's an Epic class rant I made here. It. Gets. Worse.
- There's a simple trick to deal with a universe in which the rules change. Go meta and find out the pattern in which the rules change. In other words, find the rules beneath the rules. That's pretty much how we stumbled upon Quantum Mechanics or Relativity - it appeared that the rules we know change in some circumstances, so we pulled an Inception on reality, went a level deeper and found a fuckton of weirdness that is nonetheless possible to use to find how the world works.
- In that case, I should refine the first axiom even further. 'Objects exist.' Not any specific objects, simply 'objects'. This is probably as deep as I can axiomatically get, since that premise is recognized be
every single philosophy, even solipsists recognize that premise, though in their case the object is a mind. But, if we only used that, the system doesn't support logic yet. So, axiom two, split into pieces and rehauled for the we need to go deeper axiom one:
2) '
perceivable reality is composed of objects',
3) '
perceivable reality is independent from any possible perceiver',
4) '
objects have an immutable identity'.
1) is undeniable, because to deny that
something exists, you need to exist yourself. Can be called
Axiom of Existence due to that.
(also because theatrics and hamminess for fun and profit).
2) should not be very controversial, it clarifies that the only 'things in reality' are objects, or that there are no non-object constructs - if there were, the lowest-possible-level parts they are made of would be objects themselves. Since it disallows non-objects, I'll call it the
Axiom of Exclusion.
3) is probably the most possibly controversial, but it needs to be accepted so that we could support logic. You cannot use logic in a system where you can have a situation where A && ~A = 1, depending on who is looking at A. And if we cannot use logic, none of the posts made here are meaningful.
Axiom of Objectivity.
4), again, it is a simple clarification on the nature of objects. We don't know how many levels of reality are there, but whatever is at the lowest possible level (even if it would regress into infinity!) remains unchanged in its nature. 1's and 0's don't become A's and B's, or 'red' and 'blue'.
P(W) is, in fact, P(W|B) - probability of white given bird, and P(S) is actually P(S|B). And P(B) is P(B|A) (bird given animal). Yes, I do realize that so far it's turtles all the way down, but so far I spent two hours writing this post, and my brain is about to go on strike over inhumane work conditions and unpaid overtime, so I don't want to delve into philosophy of probability just yet - I don't know about you, but what I write here is not rehearsed. Which means I have to think my way through, and I might end in strange, unfamilliar places that, however, are still by the road to my destination.
Jesus fuck. This post, without the word after the last horizontal rule (i.e. what I'm writing right now), numbers 1406 words, although counting formatting markup. I wonder if I broke the post length record yet.