Describing the impossible

[robvalue]

When we say something is impossible in reality, I think that we are often referring to our descriptive language rather than any actual limitations reality might have.

A common example is that, "A married bachelor is impossible". What we are really saying here is that if you present me with a person that I would label as being a bachelor, I would never also label them as married, and vice versa. So this is essentially a restriction I’m imposing on my own labelling system. It’s not a statement about what can and can’t occur in reality.

Another example more linked to reality itself is, "A square circle is impossible". Assuming we're not just talking about abstract theory, we are referring to patterns we might spot in reality. If we see some sort of shape, we use a label to identify it. What the statement above is saying is that if I map out a shape that I would call a circle, I would never also call it a square, and vice versa. It’s again a restriction on my labelling system only. We can similarly deconstruct the idea that, "It is impossible for god to make a rock he can’t lift".

When we make scientific statements, we would be talking in looser terms. We might say it is impossible for energy to be destroyed. I would translate this as meaning we have never yet had any evidence for energy being destroyed, and all our models indicate that this would not make sense. We're not claiming that it is literally impossible. At least, I hope any given scientist would not say that. If it did happen, we’d just have to rework our models and understanding. So we're saying it is impossible as long as our models prove to be accurate.

[vulcanlogician]

So in the case of energy being created or destroyed, I don't think scientists ever claim that it is "impossible." The merely say that it cannot be created or destroyed in an isolated system (as far as they know). The parenthetical "as far as we know" is assumed to follow all statements of scientific law, so it is never said in order to avoid redundancy.

Dark energy, for instance, may be a case of the universe breaking the first law of thermodynamics. Or it may just be an innate instability in spacetime. Scientists are still puzzling it out.

[brewer]

Do we just change "impossible" to "improbable"?

[Whateverist]

The first two cases are impossible on account of the way we define things. But the conservation of energy/matter is not part of the definition of those things, so it could conceivably be true or false and is therefore an empirical matter, a fitting question for science to investigate.

[DodosAreDead]

Do we just change "impossible" to "improbable"?

No. If we stopped giving due importance to established labels, the world would literally stop functioning.

[brewer]

Do we just change "impossible" to "improbable"?

No. If we stopped giving due importance to established labels, the world would literally stop functioning.

Well shit. Guess I need to start owning "creepy".

[DodosAreDead]

Well shit. Guess I need to start owning "creepy".

Your avatar is giving me more 'floof' vibes though.

[Minimalist]

You mean a pregnant virgin is impossible? 

The xhristards will be very upset!

[BrianSoddingBoru4]

Well, some things are impossible, at least in a definitional sense.  To take rob's first example, we define 'bachelor' as 'an unmarried adult male'.  Thus, a 'a married bachelor' is definitionally impossible.  Things of this sort are more than a labelling issue, they are a cognitive function issue.  The only way to make married bachelors possible is to redefine 'married', 'bachelor' and 'impossible'. Until and unless we are willing to do so, a married bachelor is, in every sense that matters, an impossibility.  Others:

-Canine cats

-Arctic tropics

-Wet desert

-Uneaten meal

-Non-alcoholic ethanol

Boru

[Angrboda]

The conservation of energy is actually backed by Noether's theorem. It's not purely empirical.