Historians of the Enlightenment are stymied by Denis Diderot's cloven polymathy. An insoluble dilemma arises between, on one hand, the amazing range of interests attested in his roles as both editor and contributor for the Encyclopédie and, on the other hand, his incorrigible dilettantism, in the centrifugal and often inconclusive pursuit of whatever topic came his way. We will do better to relinquish synthesis and highlight instead the multiplicity and versatility of Diderot's productive exuberance as such. We can then see how, rather than build arguments, he metabolized ideas into designs exhibiting a constantly increasing complexity that matched his inexhaustible energy. We can also appreciate his lifelong habit of writing in response to outside, and more or less random, prompts and assignments. An accidental polymath, Diderot preferred the pursuit of a train of thought over disciplined conclusiveness: witness his preference for dialogue over more integrative forms driven by argumentative power. A stranger to disciplinary methodology, he would nowadays be a journalist, not an academic.