As said by Dr. Reddy, there is so much to be gained, not from the fantasy, though that can sometimes be a lot of fun,  but from the fantasia, from the truth that is revealed from the Unknown, of course, visualization is important, but you also need to enhance, strengthen, and empower your own imagination so that those fantasias, those wonderful truths and realizations, can be as vivid and as vital and as powerful and as empowering as your own imagination is becoming.