Henry David Thoreau is the influential American author known for his quotes on life and nature. His most notable work, "Walden," reflects his philosophy of simple living in natural surroundings, advocating for a profound connection with nature. Thoreau's writings emphasize individualism and transcendentalist beliefs, encouraging people to seek meaning beyond societal conventions. His essays often critique materialism and advocate for deeper introspection and environmental stewardship. Thoreau’s intersection of philosophy, nature, and social critique has left a lasting legacy, making him a significant voice in American literary and philosophical history.