^^
"Logic in religion and relating to ALLAH" by itself is a long discussion, which i dont want to get into.
Actually, The human body is dead, but the soul(rooh,spirit) is alive.Talking about a muslim , If its a good spirit,it goes to Aalim-e-Barzakh(Roohon ka Thikana). If it was a spirit of a muslim who was more into worldly matters, then the spirit is weak and needs strength to go to Aalim-e-barzakh.This strength can be given by Reading Koran Khatam for the dead person,sadqa-e-Jaria etc.
The good spirit since lives closer to ALLAH (in Aalim-e-Barzakh), it can make dua to ALLAH.
Further more, I'd never, ever (InshaALLAH), go to a "PEER" or a "HAAJI" or "BABA POORI MURAAD WAALAY" , get on my knees, kiss their hands and touch their feet. I did that, when I had no knowledge (probably I was 13-14 then) and was just "following" the crowd.