If a person points out something to another person and that other person does the correct thing in the situation to interact with whatever then it would seem that we all perceive alike. — MountainDwarf

Agreed - and this means it is reasonable that we all perceive alike (or within a tolerance).

But, on the mental or psychological level how do we know that their perception of the world isn't more like a person with a sensory disorder?

We don't "know" but we have no good reason to believe that is the case - because, as you said, we have evidence he perceives what we perceive.

This is philosophy, and there is no proof for God, so we can't be sure.

We can be pretty damn sure, but we have to accept the fact that knowledge (in the strict sense) is impossible or at least rare, so we have to settle for justified beliefs.

Regarding solipsism: do you know anyone who is? I doubt it. IMO our basic view of the world is innate: we recognize a distinction between ourselves and everything else - and recognize that there are others like us. This is not taught. It makes sense that we'd have some such innate, relatively accurate, view of the world - because how else could our species (and our ancestor species) have survived? The only thing solipsism has going for it is that it is possible. But we innately believe it is false, and such a belief is worthy of being maintained unless rationally defeated - and mere possibility is not a defeater.

Regarding solipsism: do you know anyone who is? — Relativist

No, I just thought that it would be interesting to try and approach things from that viewpoint. I'm not a professional philosopher or anything.

We can be pretty damn sure, but we have to accept the fact that knowledge (in the strict sense) is impossible or at least rare, so we have to settle for justified beliefs. — Relativist

Ah, so there is no proof for spiritual things?

I would agree, I think that the closest thing we have as proof for the spiritual is each other.

How do we know that we all perceive the same reality?

If a person points out something to another person and that other person does the correct thing in the situation to interact with whatever then it would seem that we all perceive alike. But, on the mental or psychological level how do we know that their perception of the world isn't more like a person with a sensory disorder? And what's to say that the person with the disorder isn't the one who actually sees things as they are? If one person sees the world as it is it does not guarantee that other people do, obviously. — MountainDwarf

None of these questions have anything to do with solipsism. Solipsism is the absence of any other minds, not the existence of other minds that might experience the world differently. If anything that would be a form of realism.

A very good reason to believe that other people do experience the world similarly is because we are all members of the same species. Do two dogs experience the world similarly? Sure, but not similar to humans. The reason is because we have different types of senses. We don't have to look at our behavior as evidence of experiencing things alike. We can look at our sensory organs and find differences there that lead to differences of experiences.

It also seems to me that solipsism can never be the case. If there exists a distinction between the way things are and the way things are perceived, then that is realism, not solipsism. It seems to me that for solipsism to be true, the solipsist would know, with any doubt, that they are the solipsist and that there are no other minds.

But then how would the solipsist know this? How would God (if it existed) know that it is the solipsist? It seems to me that even God would have to be a skeptic of his own experiences. Claiming that it is omniscient just begs the question. What does it mean to be omniscient? What would it be like?

I know that I have a mind. I don't need anyone else to confirm that for me. It is self-affirming. The problem is that I don't know for sure that there are others that have minds. This itself is an affirmation of realism, not solipsism, because I would know whether or not other minds actually do exist. I don't, therefore there is a distinction between the way things are, and the way things are perceived, hence realism must be the case - logically.

Hi, i am the solipsist, so i will try to help you. with some short notes, that might help you understand, from the viewpoint of the solipsist.

We all perceive the same reality. I know it is hard to explain..
The solipsist doesn't live as a butterfly in a garden. He is the butterfly AND the garden. All others live in the same garden too, but the garden is only equal to the solipsist.

It'"s like the drop in the ocean and the ocean in the drop. The solipsist is a drop in the ocean. But everything in the ocean is also contained in the drop. The other drops only live in his ocean.

How does the solipsist know that he is god or that god is solipsist? Because he test it, to figure it out.
The solipsist is the creator in creation, but also creator and creation. So if the creator knows he is creation too, where should he go? ask that to a priest and he will reply, you are asking a really difficult question, one i never tought off.

So the solipsist test it. How? well, he suddenly figures out that his mood not only depends upon the weather, but the weather also depends upon his mood! The clouds are his toughts. A clear mind is a blue sky. When he is angry, he releases energy and the wind comes up. He can really make it storm just by playing with his mind.

I can give you many more examples, but i don't want to share all secrets. Only enough to help you out.

I can tell you, being a solipsist is magical. And you have no idea what this means. When you think of the most amazing thing you saw, it is nothing compared by what a solipsist can do. It might even shock really hard. Give you sleepless nights...

but don't worry, sleep well :)

Regarding solipsism: do you know anyone who is?
— Relativist

Hi, i am ;-) I'm not gonna prove it, or try to convince you, because that would only hurt a solipsist. But i will answer your questions.

I think, therefore I am proves that your thoughts exist, and nothing more. However, it does not prove that other things don't exist. I think you can reasonably rely on being accurate about certain emotions that you experience, even though emotions fluctuate. For example, if you feel happy, it is not possible to refute the quality of that experience, even if it is only for a moment, and later you feel a different emotion. Moreover, the "I" in I think, therefore I am" needs to be defined. Is it all of your thoughts, or only the thoughts you find agreeable. For example, if you experience a surprising piano falling on your head, and you question whether you imagined that or not, at some point it becomes evident that you did not "will" that to happen, and yet you experienced it. I think we can say that something other than "yourself" actually caused an object, that is not you to hit you. or something other than yourself caused you to have an illusion of being hit. At this point we can even begin to separate thoughts coming from the unconscious mind from thoughts coming from the conscious mind and going the step further and saying that only your conscious mind is "you" and thoughts that you expectantly and undesirably experience from time to time originate from some place other than you.