I agree, but I figured I'd draw particular attention to this lie on the off chance that op was about to give a charlatan a sum of money in a misguided attempt to assuage some grief.
If I tell you I'm your god and you should give me all your money or you won't go to heaven, you will rightly call me a liar, even though you can't really prove that I'm not.
You won't say "oh I guess there's no way to prove he's not god, so I'd better give him my money".
In science, the default stance on something existing is that it doesn't, unless there's solid proof, or at least a compelling scientific theory suggesting that it does.
It seems you are absolutely sure that dead people cannot hear or understand you, so sure that you think there can be no wiggle room.
But did you know that during the French revolution, severed heads of those executed hours ago were known to open their eyes and look at people who spoke their name?
It’s not hard to believe. It’s not like the neurons connecting the ears to Wernicke’s area magically disappear. The part of the brain which processes one’s name is known to have evolved earlier and is more basely integrated. And there’s no rule that says neurons cannot fire even once after death. Indeed, bodies are known to move or twitch hours after death – so why not there brain, where most of the body’s neurons are?
Arguments for and against: www (dot) cureus (dot) com/articles/133225-the-most-gentle-of-lethal-methods-the-question-of-retained-consciousness-following-decapitation#!/
Decapitation experiments of Louis: www (dot) cairn-int (dot) info/article-E_RHS_612_0333--the-debate-over-severed-heads.htm
“Languille!” he called out the criminal’s name. To his astonishment, the eyes lifted and “…fixed in a precise fashion on mind and the pupils adjusted… I had the impression that living eyes were looking at me”
(this isn’t hours later but it’s the first source I can find rn)
Some organisms have detectable brain activity 96 hours after death (nobody has done this experiment on a human) www (dot) sciencealert (dot) com/how-long-does-a-human-head-actually-remain-conscious-after-being-cut-off
I’m not claiming 100% that consciousness can return even for an instant after death. I just think there’s enough question marks here that it can’t be entirely ruled out.