initially perceived to be too challenging, such as learning a musical instrument or a second language,
even though sustained investments of e§ort would eventually lead to signiÖcantly accelerated rates
of learning. Such investments may come to be seen as wise with the beneÖt of hindsight, but would
not have been made by learners acting on local cues in the absence of external pressure. These are
precisely the circumstances in which guided learning can result in heightened overall performance
across a broad range of tasks relative to self-guided study