[QUOTE=davar55;314491]But I have proven that "unicorns exist" is arbitrary, because the statement
is made without definition of unicorns or evidence that "they" exist.
And arbitrariness (i.e. emptiness of conceptual content) entitles one to
conclude proven falseness.

You did start to write "they" might be hiding, which is part of a definition.
But if your example is intended to demonstrate something impossible
to disprove, due to the lack of a definition of the thing in question,
you're up against a challenge proof which requires you to define your
terms. And once you define unicorn (or god) the statement becomes
susceptible to proof or disproof.[/QUOTE]It doesn't matter [i]how[/i] you want to define a unicorn, but since you ask: It has four legs, looks like a normal Earth Pony but with one horn growing out of its forehead and wings on its back. It is yellow. Now your turn to prove that they do not live on the Moon.

[QUOTE=xilman;314434]Just because no-one has [B]yet[/B] seen unicorns, despite a modicum of effort, that isn't proof that they do not exist.
... [/QUOTE]

Depends on whether you mean real unicorns, theoretical unicorns,
or fantasy unicorns, I would think. If real unicorns exist (whatever
they are) then that would tend to prove the existence of unicorns,
wouldn't it, and disprove their non-existence. If unicorns are only
fantasy animals, then by definition no unicorn really exists, I
expect. And if unicorns are merely theoretical particles, then
further experimental bombardment is necessary.

[QUOTE=retina;314493]It doesn't matter [I]how[/I] you want to define a unicorn, but since you ask: It has four legs, looks like a normal Earth Pony but with one horn growing out of its forehead and wings on its back. It is yellow. Now your turn to prove that they do not live on the Moon.[/QUOTE]

I'll try.

From your definition, you have a concept of a creature with certain
properties but with no instances of same. The origin of this unicorn
description/definition is based on not actual experience with or
sightings of one such, but on either someone else's or your own
visual or conceptual imagination. By that genesis of the concept.
it can be considered empty of actuality of instances, i.e. no real
unicorns exist, not even on the moon. (Or Jupiter or wherever.)

I know that's brief. BTW arbitrariness is not subjective.

[QUOTE=davar55;314496]I'll try.

From your definition, you have a concept of a creature with certain
properties but with no instances of same. The origin of this unicorn
description/definition is based on not actual experience with or
sightings of one such, but on either someone else's or your own
visual or conceptual imagination. By that genesis of the concept.
it can be considered empty of actuality of instances, i.e. no real
unicorns exist, not even on the moon. (Or Jupiter or wherever.)

I know that's brief. BTW arbitrariness is not subjective.[/QUOTE]
Here and on at least two previous occasions in this discussion, you are considering what happens if the unicorn or god is a figment of people's conception, or "fantasy" as you have previously called it. Your point is that in that case the unicorn or god does not exist by definition.

But does the definition of fantasy or conception actually have anything to do with whether the object of the fantasy exists? That's debatable. But if it does, then you are begging the question about the object's non-existence. And if it doesn't, then your point is not valid.

[QUOTE=davar55;314496]From your definition, you have a concept of a creature with certain
properties but with no instances of same.[/QUOTE]You have to prove there are no instances. You can't just state it as some sort of axiom. Until you prove there are no instances then the rest of your argument is irrelevant.

[QUOTE=Brian-E;314499]Here and on at least two previous occasions in this discussion, you are considering what happens if the unicorn or god is a figment of people's conception, or "fantasy" as you have previously called it. Your point is that in that case the unicorn or god does not exist by definition.

But does the definition of fantasy or conception actually have anything to do with whether the object of the fantasy exists? That's debatable. But if it does, then you are begging the question about the object's non-existence. And if it doesn't, then your point is not valid.[/QUOTE]

The object of fantasy simply does not exist. It may be like reality, as a
unicorn as defined is like a pony, but it is not reality. The concepts of
fantasy are arbitrary and could be described any which way, because
they are not based on experience or sightings of actual instances.

I don't see how you can define fantasy to mean of things that really
exist. Fantasy is imagination, of somethings that don't exist, they
can be entertaining or instructive, but in their nature as fantasy
the objects of fantasy are unreal.

[QUOTE=retina;314502]You have to prove there are no instances. You can't just state it as some sort of axiom. Until you prove there are no instances then the rest of your argument is irrelevant.[/QUOTE]

There are no instances because the definition is arbitrary.

The definition is arbitrary because it is based on imagination and not
experience or sightings or any other evidence of any instances.

Giving a definition of something is necessary to understanding it,
if it's real. Giving an arbitrary definition of something which has no
evidence of existence doesn't create even the possibility of its
existence. Hence non-existence of such can be proved.

[QUOTE=davar55;314506]There are no instances because the definition is arbitrary.[/QUOTE]You still haven't proved that. How do you know that I did not see one with my telescope? Perhaps I did (or at least though I did) and gave what I believed to be a perfectly accurate description.

But anyhow, your argument about the state of my mind being able to affect reality does not make much sense. I wish the state of my mind [i]could[/i] affect reality. That would be a neat trick.

"There are no instances because the definition is arbitrary."

[QUOTE=retina;314507]You still haven't proved that. How do you know that I did not see one with my telescope? Perhaps I did (or at least though I did) and gave what I believed to be a perfectly accurate description.

But anyhow, your argument about the state of my mind being able to affect reality does not make much sense. I wish the state of my mind [I]could[/I] affect reality. That would be a neat trick.[/QUOTE]

How do I know whether you saw one through a telescope? Either you
did or you didn't. If you didn't, there's still no evidence. If you did, then
that "fact" should be provided as evidence along with your definition,
and its reality could then be examined by others. Confirmation, or
independent evidence, would undo the arbitrariness (if you were right).

[QUOTE=davar55;314510]"There are no instances because the definition is arbitrary."



How do I know whether you saw one through a telescope? Either you
did or you didn't. If you didn't, there's still no evidence. If you did, then
that "fact" should be provided as evidence along with your definition,
and its reality could then be examined by others. Confirmation, or
independent evidence, would undo the arbitrariness (if you were right).[/QUOTE]It is not fair to shift the discussion. I already acknowledge that for a proper argument I would be the one to prove the existence. But here I am showing that you (or anyone) can't prove the non-existence of things. You seem to keep trying to say that how something being arbitrary somehow proves it does not exist. But you don't show how this proves non-existence. You appear to be stating it as some sort of accepted fact. I could define and arbitrarily shaped cup but that in no way affects whether such a cup exists or not. Just because something is arbitrary does not automatically imply that it does not exist.

[QUOTE=davar55;314504]The object of fantasy simply does not exist. It may be like reality, as a
unicorn as defined is like a pony, but it is not reality. The concepts of
fantasy are arbitrary and could be described any which way, because
they are not based on experience or sightings of actual instances.

I don't see how you can define fantasy to mean of things that really
exist. Fantasy is imagination, of somethings that don't exist, they
can be entertaining or instructive, but in their nature as fantasy
the objects of fantasy are unreal.[/QUOTE]
That's fine. That was one of the interpretations of an object of fantasy which I indicated.

In that case, you are [I]begging the question[/I] if you call a unicorn an object of fantasy. If you want to prove that a unicorn does not exist (on the moon or universally), you cannot start from the premise that a unicorn is an object of fantasy if that in itself means that it does not exist.