It is accepted that the theme of “intentionality” highlighted in modern philosophy originated from F. Brentano who distinguished physical phenomena from mental phenomena on the basis of “intentional inexistence”. Be that as it may, he failed to thematize and terminologize “intentional” which, as a result, is replaceable by “objective”. From an empirical standpoint, set by Brentano, mental phenomena have real existence as well as “intentional inexistence”, whereas physical phenomena merely have intentional existence, and commonsense phenomena have transcendent existence. Of the three kinds of phenomena, only the mental one can be given evident judgment. The conversion of theme from “intentional” to “intentionality” in phenomenology and analytic philosophy shows later scholars’ misunderstanding and recreation of Brentano’s relevant thought.