in Thoreau’s Journal:

There are many ways of feeling one’s pulse. In a healthy state the constant experience is a pleasurable sensation or sentiment. For instance, in such a state I find myself in perfect connection with nature, and the perception, or remembrance even, of any natural phenomena is attended with a gentle pleasurable excitement. Prevailing sights and sounds make the impression of beauty and music on me. But in sickness all is deranged. I had yesterday a kink in my back and a general cold, and as usual it amounted to a cessation of life. I lost for the time my rapport or relation to nature. Sympathy with nature is an evidence of perfect health. You cannot perceive beauty but with a serene mind. The cheaper your amusements, the safer and saner.

They who think much of theatres, operas, and the like, are beside themselves. Each man’s necessary path, though as obscure and apparently uneventful as that of a beetle in the grass, is the way to the deepest joys he is susceptible of; though he converses only with moles and fungi and disgraces his relatives, it is no matter if he knows what is steel to his flint.