"Surely these experiments show very clearly how the remembrance of our dreams becomes so chaotic and inconsequent as it frequently is. Incidentally they also explain why some people — in whom the ego is undeveloped and earthly desires of various kinds are strong — never dream at all, and why many others are only now and then, under a collocation of favourable circumstances, able to bring back a confused memory of nocturnal adventure; and we see, further, from them that if a man wishes to reap in his waking consciousness the benefit of what his ego [higher self/soul] may learn during sleep, it is absolutely necessary for him to acquire control over his thoughts, to subdue all lower passions, and to attune his mind to higher things. Chapter 7"