Franz Brentano 1 was an important philosopher, but for a long time his importance was under-estimated. At least in the English speaking countries, he came to be remembered best as the initiator of a philoso­ phical position which he in fact abandoned for good and sufficient 2 reasons. His ultimate and most important contributions passed almost unnoticed. Even such a well-informed and well-prepared book as Passmore's IOO Years of Philosophy (Duckworth, I957), is open to the same comment; Passmore concentrated his attention on the early Brentano, because he regarded his influence on the British philo­ sophical scene as being confined to Brentano's early work. Brentano's pupils, e. g. , Husserl, Meinong, Marty and Twardowski, were often influential and, often enough, they departed from the strict common­ sense and advisedly cautious attitude of their great teacher. Thus even on the continent, the public image of Brentano tended to be incomplete (and sometimes distorted), outside the narrower circle of pupils, followers, and people with special interest. This, or very nearly this, was still the case in I955, when my contacts with the followers of Twardowski made me turn towards the study of Brentano. Since then there has been a gratifying revival of interest in his work. His early book on Aristotle was reprinted in German and two of his main positions, Psychologie and Wahrheit und Evidenz, are appearing in English translations. Translations into other languages, e. g.