By “entirely on belief” do you actually mean “entirely on faith,” that is, belief without evidence? Because otherwise your statement is nonsensical — people can and do make claims without knowing something, otherwise science wouldn’t exist. The key is that when a person makes a claim, that claim needs to be supported by evidence. The grandparent post is pointing to the mountains of evidence that we have regarding the brain, and making a claim regarding death causing a ceasing of consciousness.
If you want to claim that consciousness continues after death, you’d better bring some evidence along with that claim.
If you want to claim that consciousness continues after death, you’d better bring some evidence along with that claim.