Well -- by its very nature, and the fact that we're both still here "on Earth" -- not at all. Therein lies the problem with humans: assuming that everything can be 'proven or not proven': this itself is a 'belief about reality'. On your part, asking for objective proof about a subjective reality is -- as you well know -- a null statement.

I can assert things that both you and I agree can't be proven with our limited knowledge. The mathematician Godel proved this in the realm of mathematics back in the 1930's. I will assert that the same is true in the realm of 'generally accepted human knowledge about death'; that's why we're reduced to religion -- and thus subjective belief -- in this particular area. But even subjective belief is based on something -- just not "objective" truth at this time.

So I am going to further assert some things with which you may or may not agree. Operating together, they form a picture of reality which -- by the standards of scientific proof as we both agree -- cannot be proven. However, I do believe -- based on my own subjective experience -- that these things are true. Based on their own subjective experience, not everyone will agree with these statements.

'Consciousness is eternal. It is not limited by either space or time. Our experience on Earth is temporary. It is for the purposes of learning. It is necessary for this learning to appear to be real to us for it to 'take'. Each of us is a consciousness. Our appearance here is in the nature of a certain focus of that consciousness in physical matter; this is what is known as the 'ego'. The beliefs of the ego limit its awareness. The beliefs are what cause the ego to accept what is 'real'. Not all consciousnesses are limited by the same set of beliefs. Some people don't forget where they come from, but most people do. This forgetting makes the reality they then experience more 'real' for those who do. All forms of belief are legitimate. To accept something as 'real' makes it real. In this particular timeframe, materialism -- the belief that only what one perceives through the senses is real -- is a dominant mainstream belief, and the one that most people accept. Not everybody accepts it; thus different people experience different realities. All experience based on belief is legitimate.'

Perhaps you can then see why I assert that human consciousness survives death and why you don't. I further assert that your belief is legitimate, and thus -- like the classic Buddhist or atheist -- you may not experience the same reality upon 'death' that I will. However, I also believe that -- should you secretly believe what you don't care to verbalize -- you may experience that reality, and thus I have given you a 'lifeline' (if you will) to hold on to.

The proof is ultimately in the pudding, isn't it? When you 'die' -- I assume that you're going to at some time -- you will be reassured that someone was able to let you know that things would be all right -- even though you doubted them at the time. But -- because of your own beliefs -- you won't know it until then. You will feel relieved...