The special kind of keratoma found in the temporal bone, which has been called cholesteatoma by our otologic forefathers, was an unsolved problem in Virchow's time. It still is. I feel that a careful scrutiny of some classic words concerning cholesteatoma is in order. In doing so, I will paraphrase the late great philosopher, George Santayana, who stated: "He who is unaware of the past is condemned to relive it and repeat it." Von Troltch, 1 107 years ago (Fig 1), gave an early account of Virchow's examinations of the cholesteatoma, or the molluscous tumors of J. Muller, or Mollusca Contagiosa as termed by Toynbee, which occur in the petrous bone. Virchow advises the substitution of the original name ( Perlgeschewulste )— pearl tumors, which are shining, onion-like, layered tumors, in the posterior secretion of the temporal bone, which extended through the bone to the external auditory canal —sometimes, also, in