Sounds: Thoreau encourages the reader to be "forever on the alert" and "looking always at what is to be seen". Although truth can be found in literature, it can equally be found in nature. In addition to self-development, developing one's perceptiveness can alleviate boredom. Rather than "look abroad for amusement, to society and the theatre", Thoreau's own life, including supposedly dull pastimes like housework, becomes a source of amusement that "never ceases to be novel". Likewise, he obtains pleasure in the sounds that ring around his cabin: church bells ringing, carriages rattling and rumbling, cows lowing, whip-poor-wills singing, owls hooting, frogs croaking, and cockerels crowing. "All sound heard at the greatest possible distance," he contends "produces one and the same effect".