According to the Buddha, there are Six Worlds, or basic states of existence, that we can experience from moment to moment and even from lifetime to lifetime. These are the worlds or the hell-dwellers, hungry ghosts, animals, fighting demons, human beings, and the heavenly beings. Depending upon the positive or negative causes we make, the very nature of our body, mind, and environment can change to resemble one or more of these worlds. When we give in to despair or unreasoning hatred we experience life as hellish. When we are so dominated by selfish craving that we can never get enough of what we desire, then we are in the half-alive state of a hungry ghost. When we live only for immediate gratification and ignore the consequences of our actions, then we have become like animals who live only by instinct. When we puff ourselves up with pride and compete with others for money, power or sex, then we have become like fighting demons. When we are able to act reasouably and are not overwhelmed by pleasure or paain, then we are in the basic state of a human being. On those rare occasion when our desires are temporarily fulfilled and we are in a state of joyful harmony and wellbeing, then we are experiencing the heavenly realms. These different states are ever-changing and flow from one to the next.