Brentano on Intentionality

Intentionality is the most important and influential idea of Franz Brentano. He was not in fact the originator of this theory, but revived a view tracing back to Aristotle, Islamic philosophers and medieval scholastic philosophers, introducing it to the modern western philosophy but he also undertook to develop and elaborate it. This theory constitutes one of the key elements of Edmund Husserl's phenomenology.Brentano's initial view concerning intentionality appeared in his crucial work, Psychologie vom empirischen Standpunkt (Psychology from an Empirical Standpoint) in 1874. Showing preference and independence of psychology in relation to the natural sciences, he described the basic characteristic of psychological phenomena, including thought, from the physical phenomena such as color and sound as regards to intentionality of psychological phenomena. According to him, our perceptions, like seeing and hearing are always about objects which possess "intentional existence" rather than "real existence". Brentano, by making additions to 1911 edition of his work, changed his original viewpoint. In his new point of view, he insisted on the intentionality, but rejected the idea that the objects of thought possess "intentional existence" rather than "real existence". The difference between mental relation and other relations is in the fact that in the latter, such as being smaller or larger, both terms-both the fundament and the terminus- should really exist; yet in mental relation, only the person thinking is required. The terminus of the so-called relation does not need to exist in reality at all.