The dilemma named in Hugh G. Petrie's title was stated by Meno in Plato's dialogue of that name: "A man cannot enquire about that which he knows or about that which he does not know; for if he knows, he has no need to enquire; and if not, he cannot; for he does not know the very subject about which he is to enquire." Petrie argues that Meno's dilemma poses the fundamental epistemological question for education, "How is learning possible?" He examines a variety of familiar approaches to learning, from the open classroom to back-to-basics, and finds that each of these approaches attempts to grasp one horn of the dilemma to the exclusion of the other.
The examination of previous attempts to resolve the dilemma of enquiry and learning prepares the way for Petrie's proposed solution. He defines learning as an adaptation of thought and action to the demands of the natural and social world. This process has two major components, assimilation and accommodation, corresponding to the two traditional ways of attacking the dilemma. Assimilation is explained using the insights of [control] systems theory, while results in evolutionary epistemology are brought to bear on the question of accommodation. Petrie shows that only a reflective equilibrium between assimilation and accommodation will allow for a resolution of the Meno dilemma.

In the course of his presentation the author challenges a number of educational dogmas, including the beliefs that clear and unambiguous goals can be stated for learning; that theory can be "applied" to practice; that "subjective" tests are inferior to "objective" tests; and that the intelligence of a child makes a difference to educational policy. The book outlines new approaches to commonplace educational phenomena such as testing and to radical phenomena such as conversion experiences. It makes novel practical suggestions for the use of activity, perceptual training, and metaphor in a variety of learning situations.