Asserts that despite frequent attempts to barr it from the curriculum, "Huckleberry Finn," a testament to the possibility of interracial respect and friendship, is the most-taught piece of American literature in U.S. high schools. In this reprint of a 1948 introduction to the book, Lionel Trilling points to the novel's power of telling the truth and of dealing directly with human virtue and depravity as keys to its greatness.(SM)