In today's world economy, sustainability has become a significant part of life, which began many years ago in past civilizations and gradually improved and developed in today's society. After the destruction caused by the Holocaust, “How could anyone expect the human race to be governed by reason, that advances in technology and science were for the greater good, when human beings were not only capable of genocide, but also possessed the ability to annihilate oneself” (Sayre 1467). Sustainability has enabled individuals to understand their potential to sustain and improve the quality of life, thereby protecting and improving the atmosphere for present and future generations. For individuals to continue to enjoy their quality of life, they must balance their own needs with those of others and take care of their environment. Furthermore, it is about living your values ​​and demonstrating them with honesty, responsibility and generosity, because in the end everything is interconnected. Henry David Thoreau is one of the best-known American writers who wrote, Life without Principle, which illustrates the belief that people of integrity have their own freedom that allows them to follow their own personal opinions. This can be represented in a passage from Life Without Principles. “The worker's aim should not be to earn a living, to get "a good job", but to do a certain job well; and, even in a pecuniary sense, it would be economical for a city to pay its workers so well as to make them feel that they are not working for base ends, such as simply for sustenance, but for scientific, or even moral, ends. Don't hire a man who does your job for money, but who does it... middle of paper... hey, whether he likes doing his job or not. It's a shame to throw away your life working primarily for some sort of income and not appreciating what the world has to offer. People need to take a second to evaluate their way of life. They need to set their lives around themselves, not the other way around, where they live with the money they earn. Ultimately, these writers and artists both demonstrate how humanity should think before acting and not let distractions stop them from enjoying life. Works Cited Durand, Asher B. Kindred Spirits. March 15, 2007. Web. May 25, 2011. Sayre, Henry M. The Humanities: Culture, Continuity, and Change. New Jersey: Pearson Education, Inc. 2008Thoreau, Henry David. Life without principles. August 9, 2009. Web. May 25 2011. .