Does anyone know what a "soul" is? What I mean to ask is, is there some science that states that humans have a soul or a conscious? Well actually I'm pretty sure there is no proof and there probably never will be. But I want to know why do we believe that humans are the only ones to have "souls"? Also I saw a youtube clip of Michio Kaku who didn't really give his opinion on afterlife, but to me it seemed like he hinted at a possibility of our "soul" to pass onto another dimension upon death based on the m-theory. Now he kind of said the soul of a human could be an energy that can only be perceived in the higher dimensions. Now I have another question, hypothetically if we were to have a soul that passed on to higher dimensions(not heaven or hell), when did humans obtain this characteristic, did we evolve somehow? Did the first cells to use oxygen have a soul?(sounds stupid) My opinion is that we really only have this lifetime, but that is my opinion and I am definitely open to change my views. I do know that I will probably never believe in a personal god, or a jesus type god. Thank You, I'm 18 and a whole life ahead of me, but these things bother me. My dad's 57 and I love him and I don't ever wanna see him leave.