 This picture of how rational abilities in general are to be explained, including the ability to speak a language, was called into question by Ryle in a number of early papers (especially in 1946a, ostensibly reworked as the second chapter of 1949a, and in 1946b and 1950). It was also called into question by Wittgenstein in his discussion of rules (Wittgenstein, §§143–155 and 179–202).