. For the importance of problems, see M. Bunge. Scientific Research (Berlin: Springer Verlag, 1967), chap. 4. For the importance of problem situations, see W. W. Bartley III, “Approaches to Science and Skepticism,” Philosophical Forum 1 (1969): 318–31.

. The word “suggest” is too mild here: the depressive qualities of these doctrines bring to mind the brainwash techniques discussed in Sargent's The Battle for the Mind.

. For more detail, see my “Science in Flux,” Boston Studies in the Philosophy of Science 3 (1968):293–323, and my “Unity and Diversity in Science,” ibid. 4 (1969): 464–522.

. For more details, see my “The Nature of Scientific Problems and Their Roots in Metaphysics,” in The Critical Approach: Essays in Honor of Karl Popper, ed. M. Bunge (New York: Free Press, 1964).

. New York: Charles Scribner's Sons, 1967.

. Boston: Little, Brown & Co., 1967.