Seer, forecaster, prophet, geomancer, or tout - all predict future events as physicians must. The medical activity is prognosis from the Greek pro (forward) and gnosis (special knowledgeL thus foreknowledge, and the practitioner is the prognosticator, a sobriquet which falls unhappily upon the ear. Like it or not, there is nothing more critical in the management of chronic rheumatic conditions than a reasonably clear picture of what time and disease will bring. The knowledge is so much a part of ordinary medical thinking that we rarely grace it with the label prognosis. But, like so much of...