“Nothing is real and nothing to get hung about”
‘Strawberry Fields Forever‘, The Beatles, John Lennon and Paul McCartney, 1966
Given God’s religious definition, it is impossible to prove the existence of God.
Part 1 – Some definitions and basic conclusions
Rene Descartes‘ idea of our entire world being no more than something found in our mind, is well demonstrated by the famous ‘Brain in a Jar‘ thought experiment (also known as ‘Brain in Vat‘):
Imagine that when you are deeply sleeping at night, an evil scientist arrives at your room. Without waking you up, he carefully removes your brain from your skull, while keeping it alive, floating in a jar of nourishing substance, and connecting all required neurons to a super-computer. The computer, using some complex and sophisticated software, feeds your brain with electrical signals, similar to those it was accustomed to before, thus mimicking ‘virtual reality’.
You feel as if you wake up in the morning after, and experience various things. You may sense walking in the street, seeing the weather gets bad and rain starting to fall. You eat something sweet that you like. In practice, these are all illusions – caused by the electrical signals sent from the super-computer, as part of its ‘conversation’ with your brain in the jar, under our scientist’s control.
At his discretion, the scientist may generate a totally different reality for you. Rain will be replaced by a sunny day, sweet by salty. If he wishes so, he can bring real ‘miracles’ into your reality: The Sun may rise in the west and set in the east, and you may be able to fly high in the sky or dive deep in the ocean. As far as you are concerned, all these are absolutely realistic. The scientist and his computer may even erase whole periods from your memory, bring you back in time to experience other events instead, and you will never be able to tell the difference.
Two issues in this story are worth some elaboration.
The first one is the scientific method. It teaches us to objectively research natural phenomena in order to understand their meaning and the laws of nature behind them. We need to conduct controlled experiments and measure their results using objective tools. Yet, in our ‘Brain in a Jar‘ story, even if we conduct such experiments and are strict in keeping all the rules, still their outcome will reflect the specific laws of nature dictated by the software in the scientist’s computer, and those may be totally different than the laws of nature in the scientist’s own world.
The second issue has to do with our inability to know we are under the influence of the scientist’s computer. According to what we feel as well as the results of our possible scientific experiments, we will reach the conclusion that our experiences constitute the one and only reality.
By summing up these two issues, while in the ‘Brain in the Jar‘ scenario, we reach the inevitable conclusion about every other entity except ourselves: We can never absolutely distinguish between the following three options: (a) The entity does not exist; (b) The entity exists, but has no consciousness and self-awareness; (c) The entity exists and possesses consciousness and self-awareness.
Part 2 – Continuing with the proof
Logically, there can be exactly two possibilities: ‘God’ exists, or ‘God’ does not exist.
If it does not exist, then it is impossible to prove its existence (since from such a proof we will conclude its existence, and we are dealing with the case where it does not exist).
If it does exist, then by definition it is also (i) ‘almighty’ (in human terms) and (ii) possesses own consciousness and self-awareness. The technological capability of our evil scientist is (by definition) inferior to that of ‘God’. Therefore we can conclude it is possible (as superior capabilities are possible). Hence, all our conclusions derived from the possibility of such capability are also true.
One of these conclusions was our inability to prove that any other entity except ourselves exists and/or possesses consciousness and self-awareness. In particular, we cannot prove that a conscious ‘God’ exists outside ourselves.
Hence, in any of the two possibilities above, it is impossible to prove the existence of ‘God’.