It is a very small number of dreams that can be so explained that they arise by external stimuli and in many cases the explanation is quite arbitrary or cannot be proved. A much larger number of dreams arise from subconscient impression of the past without any stimulus from outside. These are the dreams from the subconscient which are the bulk of those remembered by people who live in the external mind mostly. There are also the dreams that are renderings of the vital movements and tendencies habitual to the nature, personal formations of the vital plane. But when one begins to live within then the dreams are often transcriptions of one's experiences on the vital plane and beyond that there is a large field of symbolic and other dreams. There are also prophetic dreams and many others.

The entire oblivion of the experience means merely that there is still no sufficient bridge between the inner consciousness which has the experience in a kind of samadhi and the exterior waking consciousness. It is when the higher consciousness has made the bridge between them that the outer also begins to remember.

There was no issue from that dream like space.
Our being must move eternally through Time;
Death helps us not, vain is the hope to cease;
A secret Will compels us to endure.
Our life's repose is in the Infinite;
It cannot end, its end is Life supreme.