Therapeutic Evolution or Revolution? Metaphors and Their Consequences

Evolution and revolution are both models of change over time. It is easy to see the appeal of a claim of revolution for scientists and for their historians: it pronounces a radical break from the past, confident and triumphant. Progress is implied by the decisiveness of the rupture. Such rhetoric is good for marketing, especially when contrasted against the cautious gradualism of evolution. But evolution has its own appeals, especially its reassuring connotations of progressive improvement. It is not enough simply to debate what counts, or not, as revolution or evolution. Instead, much can be gained through serious engagement with the theory and language of revolution and evolution in pursuit of the best possible accounts of scientific change.