Read the following excerpt from Walden by Henry Thoreau and write a paraphrase of his claim.
By the words "necessary of life" I mean whatever, of all that man obtains by his own exertions, has been from the first, or from long use has become, so important to human life that few, if any, ever attempt to do without it. To many creatures there is in this sense but one necessary of life, Food. The necessaries of life for man in this climate may, accurately enough, be distributed under the several heads of Food, Shelter, Clothing, and Fuel; for not till we have secured these are we prepared to entertain the true problems of life with freedom and a prospect of success.