without the creative power of thought we cannot organise the body in the world which is nearest to the physical. Now, supposing that we recognise that our consciousness working in the physical brain, the instrument over which we have complete control, is continually at work contacting the outer world, using the brain as an instrument on which it can play, and continually bringing down from higher worlds impressions which it transmits more or less perfectly to the physical plane, we need not dwell upon our ordinary thinking. Let us take thinking a little more unusual, where the finer part of the brain, its etheric matter, is being more largely vitalised, more definitely used. The powers of the imagination--the creative power--the artistic powers, all creative in their nature, these utilise most the ethers of the brain, and, by working in those, bring into activity the lower and coarser matter of the dense brain. Now, the thought passes from the consciousness through vehicle after vehicle to find its clear expression here. But do you not have many mental impressions that are not clear, not well defined, and yet which impress you deeply, and of which you feel sure? They are of many kinds, and reach you in many ways. What is important to you is simply this for the moment: that being surrounded by the astral and mental worlds, contacts from these are continually touching you, continually causing changes in your consciousness. If your astral body were thoroughly organised like your physical, the impressions made would be clear and sharp like the physical. If your mental body were well organised, the impressions of that plane, the heavenly plane, would be clear and sharp like the physical. But as the astral and mental bodies at this stage of evolution are not well organised, the impressions received by them, causing changes in the consciousness, are vague and indeterminate, and it is these which are generally called "psychic." And when you have a Psychical Research Society, it is not dealing with the ordinary processes of thought, but with those which are not ordinary; and all those things to which it gives many strange names are all workings of the consciousness, in sheaths or bodies of which it has not yet gained the mastery, which it has not yet definitely organised for its purposes. Slowly and gradually they become organised, and strenuous thinking is the method for the astral body, and the working of the pure reason is the method for the mental body. Let us consider with regard to this, whether there is any other way of bringing the astral body and mental body into activity. For you may have noticed that I used the word "normal" evolution, orderly evolution on the lines of natural evolution, always from above. But you may stimulate it from below. It is possible to stimulate the astral body, at least, from the physical plane, but you do it at the cost of higher evolution a little later on, and the reason you can do it is simple enough.