Avoiding debates & looking into Planes/realms
The planes of existence can known as psychological states of mind therefore it is easy to prove them to others. People have hellish suffering; people behave like animals; people can be ungrounded rootless ghosts &amp; addicts; people can live a godly life of wealth, power, luxury or bliss; people can be humane. 

Planes of existence are depicted below. An explanation is: The Wheel of Life by Barbara O'Brien.