The Spirits' Book
Book Two - The Spirit World
Chapter XI - The Three Kingdoms
Animals and Humans
609. Once they have entered the human period, do spirits recall any traces of what may be called the “prehuman” period?
“That depends on the distance between the two periods, and the amount of progress accomplished. Over a few generations, there may be a more or less clear-cut refection of the primitive state. Remember that nothing in nature ever happens abruptly, and there are always links uniting the ends of a sequence of beings or events. Those traces disappear with the development of free will. The first steps of progress are slow, because they are not yet supported by the will. As spirits acquire a more perfect consciousness of themselves, progress accelerates.”