Spirituality, (as in religion, ghosts, supernatural and all that bullshit) is based on superstition, bred by lack of education and wishful thinking, and promoted by abject institutions like the church. Why would you bring up such nonsense? You question science but accept the existence of bullshit like the supernatural. One might think you are just joking. Are you?
What happens inside the grave? Let's keep it simple: a skull full of maggots doesn't sense shit!