This article argues that an important source of the difficulties posed by particular concepts and theories is the narrow range of "types of causal models" with which most learners are familiar. Most learners are familiar with relatively simple styles of causal models, but many concepts and theories in science depend on styles…

Offers insight into the sorts of questions that might be asked in scientific inquiry and suggests a new sort of question--What If?--complementary to those questions which have traditionally dominated scientific practices. (PVD)