Although studies of Thoreau by such twentieth-century scholars as F. O. Matthiessen, Sherman Paul, and Walter Harding have made his writings very popular in university and literary circles, the often hard-hitting truths that Thoreau presents in his books and essays have attracted by themselves a widespread audience. Dr. Martin Luther King, Jr., acknowledged his personal debt to Thoreau's thought-provoking essay on civil disobedience by declaring that, "I was so deeply moved that I re-read the work ["Civil Disobedience"] several times. . . . No other person has been more eloquent and passionate in getting this idea across than Henry David Thoreau. As a result of his writings and personal witness, we are heirs of a legacy of creative protest." In India, another civil rights leader, Mohandas Gandhi, was also stimulated by Thoreau's writings. Gandhi admitted that "his ideas influenced me greatly. I adopted some of them and recommended the study of Thoreau to all my friends who were helping me in the cause of Indian independence. . . . There is no doubt that Thoreau's ideas greatly influenced my movement in India." In 1962, Rev. Trevor Bush, a leader in the protest movement against the racist policies of the South African government, also acknowledged a similar indebtedness to Thoreau: "His influence in South Africa has been extremely important and our struggle to win rights for the oppressed non-white population of our country has been assisted profoundly by the fearless liberal teachings and example of . . . [this] great philosopher and prophet." These are only a few of many examples of Thoreau's influence on social action in America and abroad, and his consequent popularity. It is likely that Thoreau will continue to have a large audience among those who are searching for timeless truths that can be applied to man's situation. As philosopher Martin Buber has pointed out: "Thoreau expresses exactly that which is valid for all human history." In Thoreau's writings, one may discover that literature may be very much connected with real-life needs; one may find that art can be immediately relevant to everyday personal and social concerns.
One of the most extraordinary instances in which the popular appeal of Thoreau's thought has been recognized is related by Walter Harding in The Variorum Civil Disobedience. Citing examples of official resistance to Thoreau, Harding writes that, "when, in the mid-1950s, the United States Information Service included as a standard book in all their libraries around the world a textbook of American literature which reprinted Thoreau's 'Civil Disobedience,' the late Senator Joseph McCarthy of Wisconsin succeeded in having that book removed from the shelves of those libraries — specifically because of the Thoreau essay."
As may be seen, Thoreau has not been ignored during the twentieth century, by either friend or foe. The twentieth-century mind, whether in agreement or disagreement with Thoreau, has found in his writings an engaging intellectual challenge which cannot be ignored. In his anti-materialism, his transcendental optimism about the nature of man, and his view of society, Thoreau sharply questions the basic assumptions of modern American life. In Walden and "Civil Disobedience," Thoreau asks the "hard questions" about the way in which modern man lives, and they are questions that may be only temporarily avoided by intelligent men. Sooner or later, one must formulate a position in regard to Thoreau's view of the relationship between the individual and the state as expressed in "Civil Disobedience." Eventually, one must evaluate the anti-materialistic, spiritual view of life found in Walden. Thoreau's writings strongly invite us to think and respond; and in this lies a main cause for much of his present popularity.