Acclaimed theorist and social scientist Donna Jeanne Haraway uses the work of pioneering developmental biologists Ross G. Harrison, Joseph Needham, and Paul Weiss as a springboard for a discussion about a shift in developmental biology from a vitalism-mechanism framework to organicism. The book deftly interweaves Thomas Kuhn's concept of paradigm change into this wide-ranging analysis, emphasizing the role of model, analogy, and metaphor in the paradigm and arguing that any truly useful theoretical system in biology must have a central metaphor.