“In praise of solitude”. Lots of people have written about it. The following list begins with four individual impressions then moves on through Thoreau and official psychology to a couple of Buddhism sources. The transpersonal dimension is not always appreciated. Contemplatives unite - yoh!
http://www.salon.com/news/opinion/garrison_keillor/2009/06/24/solitude
http://zenhabits.net/creative-habit/
http://www.scotthyoung.com/blog/2009/02/16/in-praise-of-solitude/
http://www.cfidsselfhelp.org/library/in-praise-solitude
http://thoreau.eserver.org/walden05.html
http://www.psychologytoday.com/articles/199802/the-call-solitude
Shantideva
http://www.tricycle.com/dharma-talk/cutting-ties-the-fruits-solitude
Wander alone like a rhinoceros
http://www.accesstoinsight.org/tipitaka/kn/snp/snp.1.03.than.html