The system of Rogers is about a natural spontaneous actualisation. This process he called organismic, because it is natural to the way organisms function:
Let me point to some of the work in biology that supports the concept of the actualizing tendency. One example, replicated with different species, is the work of Driesch with sea urchins many years ago. Driesch learned how to tease apart the two cells that are formed after the first division of the fertilized egg. Had they been left to develop normally, it is clear that each of these two cells would have grown into a portion of a sea urchin larva, the contributions of both being needed to form a whole creature. So it seems equally obvious that when the two cells are skillfully separated, each, if it grows, will simply develop into some portion of a sea urchin. But this is overlooking the directional and actualizing tendency characteristic of all organic growth. It is found that each cell, if it can be kept alive, now develops into a whole sea urchin larva — a bit smaller than usual, but normal and complete.
I choose this example because it seems so closely analogous to my experience in dealing with individuals in a therapeutic relationship, my experience in facilitating intensive groups, my experience of providing “freedom to learn” for students in classes. In these situations the most impressive fact about the individual human being seems to be the directional tendency towards wholeness, toward actualization of potentialities. I have not found psychotherapy or group experience effective when I have tried to create in another individual something that is not there, but I have found that if I can provide the conditions that make for growth, then this positive directional tendency brings about constructive results.
— Carl Rogers on Personal Power (1977)
This “positive directional tendency” is referred to by Stanislav Grof as “holotropic”, meaning “wholeness-seeking”. Grof (like Maslow) found holotropic tendencies in his work on transpersonal experience too, indicating that the principle holds for spiritual development, to which a Rogerian beginning naturally leads later.