Hmm, well, I wouldn't say it supposes
perfect exchange and communications, but enough exchange and witnessing of the expression of other consciousnesses to have the supposition that others are conscious as well to be one that is not only possible but truly overwhelming, oftentimes in a glorious manner—and when it comes to tender empathy, often in a touching at times wistful manner too.
Our immediate experiences and past experiences form databases of information within our brains, that our brain pulls from and processes; and this available range affects the emotions and ideas that can form within this "personal frame" we have. If candid communicational experiences are sufficiently few and far between, an idea like solipsism can become more appealing due to its refuting evidence being further from sight.
I would argue that the existence of art in general is enough proof of consciousness outside ourselves though, but that would be another tract, haha :).
I sincerely offer respect for investigating the root causes of these ways of thought; it's something I've done in some other posts of mine, but it's something I neglected to touch upon here, haha; so, thank you for covering that crucial aspect :).
Absolutely! Principle of explosion :). If one has one equation that can solve literally everything, that can derive literally any conclusion, without
any hitch, it's likely an insane one.
Ultimately, I agree with the whole body of your post. It draws important attention to this key fact: ideological viewpoints often derive from
emotional experiences as well, which are usually
life experiences. A person's experience with other people
totally influences how they think about those other people, and to extents even people in general too.
I would like to conclude that fantastic second sentence, an absolutely stellar footnote to the philosophical aspects of this affair, with this quote from
Infinite Jest~ :)
For a key point in the premises as well—the bases which we are operating from.
And the frame of reference that operation begins within is a key factor to be considered as well, for that provides the environment, drives, and affects affecting the inquiry as well. Our own personal frame of reference (influenced by personal experiences,
especially those with other people) truly does have a real effect on our thinking methods and thinking preferences—and it is more lucid to nod to the origins of ideas such as this when discussing them, as to give a more lucid etiology of the matter at hand. And I sincerely thank you for bringing this critical function of the matter to hand. May we all make our own personal contributions in any ways we do towards a more lucid etiology of things :)

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