Something more in the forest than books

Believe in my experience, you will find something more in the forest than in the books. The woods and the rocks will take you to what you cannot learn from any master. Do not you think that you can suck the honey from a stone and oil from the hardest rock? Do no the mountains distill the sweetness? Do not milk and honey flow from hills, and do not valleys contain wheat in abundance?

Letter from Bernard of Clairvaux to Abbe Vauclair (12th century).