All "life-units" each, as mentioned above, elicit vibrations. As these vibrations vary, the "life-units" can be divided into types according to the character of the vibration they each represent. And it is on this mutual difference in types that everything coming under the term "evolutionary steps" is based.
      Everything in existence thus constitutes vibrations. Vibrations are in turn based on life-units. The life-units are to be found on an endless scale of steps, since there is an endless scale of different, more or less prominent, types of vibration. The terrestrial human being thus represents one particular type of vibration on this ladder. These different vibrations are mutually dependent. This in turn means that our daily vibration, which is the same as our daily manifestation and experience of life, cannot possibly take place through our own vibration alone but is determined exclusively by a mutual cooperation with the vibrations of the other beings in our surroundings. If this cooperation is harmonious, our life will be perfect. If it is disharmonious, our life will be mutilation and suffering. Knowledge of these life-units and their vibrations, on which a life in perfection for the terrestrial human being depends, is therefore the necessary condition for reaching absolute health of mind and body. So a perfect, happy existence depends not only on good co-operation with the life-units in existence that we perceive as our "fellow beings", such as people, animals and plants, but is also to the very highest degree determined by our co-operation with the life-units that we do not usually regard as living beings, namely the life-units that to physical sight show themselves as "animal" and "vegetarian" "substances". And we will therefore, in what follows, make acquaintance with those of these life-units that are for, and those that are against, the terrestrial human being in his daily journey through life.