Intentionality And Its History
The concept of "intentionality" in this modern sense was reintroduced into philosophy by Franz Brentano (1874), who took the notion from the medieval scholastics. Brentano used the German expression Intentionalität, derived from the medieval Latin intentio, which meant what we nowadays call an intension or concept and which comes from the classical Latin tendere, meaning to aim at something. Brentano thought that intentionality was "the mark of the mental," and because he thought that intentionality could not be reduced to anything physical, dualism seemed to follow; a world of intentional phenomena, the mind, is distinct from the world of physical phenomena.
Edmund Husserl (1900), a student of Brentano and the inventor of phenomenology, made the investigation of intentionality his main philosophical project. Husserl's method was to suspend the assumption that there is a real world on the other side of our mental acts (this suspension he called the époche, or phenomenological reduction) and examine the structure of and thus the intentionality of the acts themselves (this structure he called the noema, plural noemata). In Anglo-American philosophy, the topic of intentionality was introduced in large part by Roderick Chisholm (1957). Chisholm was influenced by Brentano and attempted to produce a linguistic criterion of intentionality. In addition to his writings on the subject, he edited a collection of works by Brentano, Husserl, and others (Chisholm, 1960) and conducted a lengthy published correspondence on the topic with Wilfrid Sellars (Chisholm and Sellars, 1958).
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