In Language, Truth, and Logic, Sir A. J. Ayer presents a modified version of logical positivism that he prefers to call “logical empiricism.” However, the doctrines, particularly their implications for philosophy, are largely those of logical positivism, and the work serves to bring these together succinctly and vigorously. Therefore, the book has had great importance as a positivistic document and as a center of controversy about positivistic tenets. In it, Ayer offers to solve the problems of reality, perception, induction, knowledge, meaning, truth, value, and other minds. He presents no great new idea; rather, he has modified and brought into logical consistency solutions proposed by others. In the introduction to the 1946 second edition, Ayer provided further explication and modified a few beliefs, but essentially his position remained unchanged.