R. S. Peters and Paul Hirst were the most influential figures in philosophy of education in the 1960s, 1970s and 1980s. The claim in this paper is that their rationalist's approach was often misleading and unilluminating. They believed they were preparing children for life beyond school, but to a large extent they failed because they did not take into account the diversity of values and practices of life in general. The paper contains some reflections by Rush Rhees, a student of Wittgenstein, on some of their writings. Rhees had first met Wittgenstein when he attended his classes in 1936. They formed a lifelong friendship, and Rhees subsequently devoted much of his life to the dissemination, interpretation, and criticism of Wittgenstein's work. The reflections discussed here derive primarily from views Rhees expressed in the 1970s.