Everyone who writes anything--even non-fiction!--knows you discover things as you go along. Writing is a heuristic. Writing history is no different. Yet senior-secondary and tertiary exponents of the teaching and learning of history are often strangely tongue-tied on the matter of writing and thinking as engines of discovery in historical studies in particular, and in the humanities and sciences in general. The quirks and customs of the actual research and writing practices underpinning knowledge of histories, whatever the genre, are less often modelled and explicitly discussed in advanced classrooms than the products of the historical research, the so-called history 'content'. This essay re-considers the theory and practice of writing essays in general, and history essays in particular. Specific ways in which writing enables discoveries and ways in which it deepens interpretations are explored. Conclusions are derived for a better agenda, other than offering more content, for an advanced-level history education.