It just occurred to me that people are the closest thing (as far as we’ve been able to determine) that the Universe has to a consciousness of its own existence. To our present knowledge, humans are the only beings in the Universe capable of such a degree consciousness as to be able to contemplate anything beyond immediate surroundings. Also, human beings are obviously a part of the Universe, much as any bean can be said to be a part of a beanbag chair. Thereby it follows that – to our present knowledge – there is no other entity in the Universe that is aware of the Universe’s existence.
As conscious entities in this Universe, then, if we were to disappear, and if there are indeed no other beings in the Universe conscious of its existence, there would be „nobody” left to know that the Universe exists.
But then how do we define existence? Does anything exist if it is outside of a consciousness’ possibility of grasping its existence? Think about it – if I say something exists, what I mean is that I am aware of some sort of manifestation of that something, which makes me believe that it exists. It’s the same for a rock as it is for God or aliens. The rock manifests itself through shape, color, texture, size, weight. You believe it exists because you can see the properties that it manifests. As for God and aliens, they might or might not be able to manifest themselves in the same way that a rock does, but by way of sheer belief, they do exist.
To what extent would aliens exist if nobody believed that there were any? To the same degree that a rock would exist if it didn’t manifest in a way that we could see or touch?
It would seem very arrogant of us humans to believe that existence is limited to what we can perceive with our senses. Our senses have evolved to serve us in the environment that we happen to have developed in. We have eyes to perceive light, taste buds to perceive whether something is edible or not, smell, touch and hearing – all have evolved for survival purposes in this environment.
Many of the instruments that we’ve engineered using our intelligence have mostly only enhanced our own senses. We can now see much smaller things, or things that are much farther away. Some instruments that we’ve built can also perceive things that are „new” to our species, like electrical current. It’s likely that if the Earth had been a place filled with some sort of electrical „traps” back when we were still apes, (or even before that) if we would have survived at all, we would have evolved the ability to detect electrical current. But it wasn’t, so we didn’t, so we can’t.
Whereupon an interesting question arises: what if there are „things” that exist in our environment that do not manifest themselves in any way that we are currently capable of detecting, using all of our senses and all of our tools?