It has been debated amongst philosophers for centuries, the question about the self and consciousness is one of the biggest misteries that exist. Let's analyze different subjects shall we:
1) Solipsism
Solipsism is the belief that only I exist. It doesn't have any rational argument behind it, because it's impossible to prove or disprove it. I know that I exist, and that is really the only thing I know. I see that you exist, I hear that you exist, I smell that you exist, I can sense that you exist, but I cannot know for sure that you exist. You can only be a figment of my imagination, a persistent illusion or a mirage. There is no way to prove your existence, you could be just a philosophical zombie, an entity that is behaving like it has consciousness, but in truth it doesn't.
Because it's impossible to prove that other people have consciousness, it is implied, because the same way that I know about myself, I imply that it's the same for you too, but I cannot prove it, there is no mechanism to prove it, and I can't even imagine a mechanism that would do it, because my consciousness can never "join" with yours.
So the bottom line is that Solipsism is at least true for me, I know for sure that I exist, and proof of your existence will always be beyond my reach.
2) Subjective Idealism
Another perspective, and perhaps and extension of Solipsism is the concept of Subjective Idealism. Subjective Idealism is the belief that only consciousness exists and the mental realm, and that the physical realm is the illusion. It's not contradictory to Solipsism and it's not the same but perhaps an extension of it. I still know that I exist, and I imply that you exist, and it all exists in our minds, sort of like our minds are interlinked, and the physical link is the common ground.
My personal mind is private, and the outside world is the place where all minds interact with eachother, be that human,animal, plant, or bacteria. Even the inorganic material is a mind, a proto-mind. It implies that the entire universe is a mental thought, a sort of web of consciousness of all beings and objects in it.
Everything material is just an illusion, it all happens in the mind. It is different from the belief of absolute idealism or pantheism where the entire universe is thought of as 1 entity, which may or may not be true, but in this thought it's more like a distributed web of minds.
I personally think the Subjective Idealism is very plausible, and we can clearly see examples in Quantum Physics sort of hinting towards it. The famous Double-slit experiment can easily be explained by this philosophy, and the misteries of the universe can be unlocked if we embrace it.
It still doesn't disprove Solipsism, but I find it healthier, because Solipsism can lead to super-egosism and schizophrenia, which is clearly not a healthy philosophy.
Universe is a network of consciousness!
Most of the people that are aware of their consciousness end up understanding this! :)
True, but you can never truly know your consciousness, just as fire can't burn itself or a knife can't cut itself. The observer is always beyond reach.
This is a very interesting subject, I have more articles to write about this, stay tuned!
You are nothing. You are everything
Yes, nothing = everything because there is no nothing, which is a negation to the fact that everything is everything.
It's a logical trick, but it's true.