Human beings received various sensory organs for perceiving the various areas of their environment. These areas of perception are very limited, but sufficient for human life on earth. Other beings have other areas of perception, e.g. bats and dogs can hear different frequencies than humans. Snakes and insects also perceive other light frequencies than the human eye can see. The light frequencies visible to the human eye are only a small part of that what surrounds you, as your scientists can tell you, too. In addition to the visible light, there are X-Rays, infrared light and those frequencies that transmit radio and TV broadcasts, and there are many more, yet undiscovered finer light frequencies, that are hard or impossible to detect with physical means. The spirit world consists of such invisible and undetectable frequencies, just as the frequencies of worlds on higher levels including higher developed beings from such planets. Because of the limited ability for perception and influence on the surrounding frequencies, it is however possible to develop the senses that are able to perceive other areas, and have an influence on them.