Three stages
The stages of mental development can also be conceived of in this way:
The first stage: Concentration
The power of focussing the mind is developed and enjoyed. One begins to learn what is possible with such a mind and begins to look beyond accepted ways of thinking. This stage roughly coincides with the realms of form.
The second stage: Contemplation
Reason is developed and the ways of Nature are more thoroughly understood. This stage coincides with the realms of the formless.
The third stage: Meditation
When intellectual understanding of Reality is perfect and Faith is lion-like one proceeds beyond the finite. Now at last, true meditation is possible.