Not an answer as such but a reaction to the kind of question posed.
There are some things we know we do not know, some of which are temporary conditions constrained by technology or limited cognition. Of these there are things which we know we one day can know, based on the pattern of progress we have made to date. Certain stars are beyond our sight, but we build ever more accurate lenses to pierce the cosmos.
Then there are things we know we can never know. Often times these are considered matters of faith. More often than we'd like these faith issues are used or abused by powers that be to influence policy and coerce their people. But the things we cannot know can still be glimpsed in the things we do know, whose cause we could attribute to that very thing we don't know.
A case in point can be found in the study of the cosmos. So much of the unknowable and unseeable is informed and inferred by the motions of certain bodies near and around them. Black holes are by their very nature invisible, but they operate under the same principles of thermodynamics and gravity as anything of this [macro] universe does. So by studying the patterns of behaviour associated with an 'unknownable' thing we can use that which is known, in its vicinity, to an extent that we can more-accurately-than-not know that they are there.
Similarly I feel we can observe the patterns in and around faith issues. We can inform ourselves with data, historical facts and reasoned debate. We can assign realistic probabilities to the causality of anomalous occurrences, of things seemingly magickal and supernatural. We can spend our entire lives collecting these experiences and speculative evidences but ultimately the only way to know the unknowable is in your heart. To feel its truth apparent in your being in way that stands up to the most stringent inner honesty.
Short of faith and integrity, you could always ask the entity of which you seek to reveal itself in the flesh. Good luck.
~Nephil_Improv.
--- In , "akristakos" <akristakos@... wrote:
How do we know for sure that Satan is real? What is some evidence we see in real life?