It is not everyone that can visualize. When there is no power to visualize, it is because things seen that way seem so vague and unsubstantial compared with the things which we see in the external world. We can never think of such visualized things as real. Everything that is before your eyes and ears - that is what we consider the real thing, whereas whatever comes before the mind's "eye" we regard as imagination, something passing, a dream. It is the same mind that perceives and hears the things of everyday life, yet what it perceives, the other way, we think is just imagination - for all that, it is these that are the realities!