# Self contradictory things that can't really exist: can they be fully conceived of?

It seems like we can conceive of self contradictory things that can exist. e.g. the proposition expressed by "this sentence is false" is self contradictory but I don't seem to have any trouble understanding the sentence. e.g. Lazerowitz says that there it is straight-forwardly true that self contradictory propositions "exist" if we mean "declarative sentence".

However, what about self contradictory things that's parts can't really exist? I would say we may be able to vaguely imagine them, but not fully grasp and conceive of them or their meaning.

Am I right?

Supposing inconceivability amounts to lack of knowledge, it would make sense to me to say that things that are self contradictory to us must exist empirically to be conceived of, to be known, rationally or empirically.

Maybe that's why triangles without 180 degrees of angles were, like round squares, thought inconceivable: because mathematicians couldn't see how it might apply to the world.

[Hilbert] was also partly inspired by work on non-Euclidean geometry, which at the the time was still completely controversial since it didn't seem physical. Now we know that it is physical

But that is complete guess work.

The example I am thinking of, why I ask, are Ron Silliman's poetic "effects", as they appear in his 1970s book The New Sentence. You can find the following claims:

1. a device changes the whole
2. there is really no such thing as a whole
3. effects are aggregated devices
4. effects can be self contradictory

I believe it follows that any "effect" (so defined) may be more than our conception of them, may be working outside of our conscious processes and conceptions, if the question in the title is answered with a "no".

• can you be more specific about what's unclear please? – another_name Jun 30 at 22:16
• Not my -1, but there is no trouble "thinking" the round square either. It is thinking the concept behind the words that is troublesome. Blatant contradictions are generally taken to be inconceivable, so can't "exist". What exactly is conceivable is controversial in modal epistemology, see e.g. relevant depth and other problems, and discussions of "conceivability entails possibility". – Conifold Jun 30 at 23:12
• – Conifold Jun 30 at 23:15
• i'm confused about what could be unclear about the question. can we please work together a little, i.e. explain your votes, rather than just voting. thanks – another_name Jul 1 at 4:13
• ...Times like these I'm reminded to marvel at Plato, all those thousands of years ago, scrutinizing the cave wall, knowing full well the shadows may be cast by something so much different from what he is piecing together. - Apologies for going all... mystical. – christo183 Jul 1 at 8:06

It seems like we can conceive of self contradictory things that can exist. e.g. the proposition expressed by "this sentence is false" is self contradictory but I don't seem to have any trouble understanding the sentence. e.g. Lazerowitz says that there it is straight-forwardly true that self contradictory propositions "exist" if we mean "declarative sentence".

Strictly speaking, there are no self-contradictory sentences. Sentences don't speak themselves. We do.

So, in effect, sentences are definitely not examples of existing self-contradictory things.

However, anyone willing to assert a "self-contradictory" sentence would indeed contradict themselves, and thus, become an example of, literally, a self-contradictory thing. I'm sure most people can speak the sentence "It rains and it doesn't rain".

However, speaking a sentence is not conceiving the idea expressed by that sentence. So, can we conceive a situation where it is both raining and not raining?

Conceiving is the most abstract form of thought. The most concrete is imagining, usually relying on the visualisation of the situation. Then, I don't think anybody could imagine in this sense a situation where it would be both raining and not raining. I certainly can't visualise such a situation.

But, there is no difficulty in conceiving the same situation.

To conceive the situation where it is both raining and not raining, we only need to be able to conceive a situation where it is raining and to be able to conceive a situation where it is not raining. If we can do each, then we can conceive of the conjunction of the two. The logical conjunction. And so we're done.

Conceiving is largely a logical operation. As such, it can do pretty much all which is ordinarily discussed in the context of formal logic.

However, your question may be taken to be about the possibility of "self-contradictory" propositions. Assuming that propositions exist outside of the human mind--and this is a seriously metaphysical assumption to make--self-contradictory propositions would be examples of existing self-contradictory things.

And in this case, not only are there existing self-contradictory propositions, but there is one such for every ordinary proposition. Assume one proposition p. Then, the proposition p and not p is a self-contradictory proposition.

Thus, there would be, if propositions exist at all, an infinity of existing self-contradictory propositions. All false, obviously.

And things we can't even imagine.

• i downvoted for a few reasons, not least the complete disregard for references etc. – another_name Jul 3 at 20:06
• @another_name You do as you please but "disregard" is inappropriate here. My answer is not based on published material. Any reference would be misleading. What are your other reasons? – Speakpigeon Jul 4 at 16:08
• this is not a place for discussion, but why would sentences have to be spoken to be self contradictory? – another_name Jul 4 at 16:18
• @another_name "contradiction" literally means "to say to opposite". Sentences don't say anything, therefore, they cannot contradict. It is the speaker using such a sentence who will self-contradict themselves. – Speakpigeon Jul 4 at 17:32
• that's not true even in google definitions "(of a text or a symbolic representation) convey specified information or instructions" – another_name Jul 5 at 12:59