Here is some more info on the importance of dreams and visions

Native way of knowledge. Spiritual Visions and Dreams

http://www3.brandonu.ca/library/cjns/13.2/goulet.pdf
" in such societies one often finds well-developed traditions for inducing visions and/or lucid dreaming, traditions that are available to individuals as part of their social development.1 Such traditions seem incompatible with the ethnographer's own society's low tolerance of fantasies and of the primary thought processes in general. Hence the reticence of ethnographers to cross over to others and “enter with them into dream- land, for to do so is to venture beyond the confines of civilized man,” into a realm of experiences which white men tend to hide in asylums.

, “the empirical and logical rationality that defines knowledge as knowledge of fact” is a rationality that is not hospitable to “the insights of art, religion, fantasy, or dream.”

I will interpret for you in plain language what he is saying,he says that in other societies visions and dreams are not suppressed or discarded but valued and infact encouraged and desired because they inform,that it is only here in our society that people with visions are locked into asylums.

we only value linear,left brained thinking,but Dreams and visions are the sphere of the right hemisphere(logic and order are of the left) so you see only one side of the brain is attributed to knowledge and the other is ignored and suppressed and infact locked up.

Dreams and Visions

Dream vision - Wikipedia, the free encyclopedia