It's fact that we are all made up of trillions of atoms, and that these atoms make up the Earth as well as everything around us. So when we die those same atoms still linger and are around as part of different objects. So at some point these atoms created us (came together and formed the human we call "I"). Therefore, if just by random these atoms came about and formed you and I, and everything around us then that brings about quite a theory. We can't control our own lives. We are just part of a system where atoms "do their buisness".
beat boss by up slashing him when he's in mid air (up slash as soon as you see him jump) also, move around by slashing near you continuously, so the samurai keeps running but doesn't slash. Hope this helps! I beat the game without any upgrades or without losing any lives, but I'm playing it again for the badges and the challenge