Abstract
Very often it is supposed that Aristotle considered the two terms αγαθον and καλον synonymous. But it is a fact that he distinguishes them clearly in some passages. When considered in detail, this question is a rather complicated one and seems to have connections with other philosophically very important quetions. We do not intend here to study the whole problem exhaustively and to propose a complete and perfect explanation of every difficulty. This is impossible since the space at our disposal is too limited and since the writings of Aristotle contain some ambiguities and are far from being completely perfect and clear. Nevertheless we think it worth while to consider the most important places where this question occurs and to try to clarify what aspects of the problem attracted the attention of Aristotle and in what direction he looked for a solution. We may sum up the conclusions very briefly in the following manner; Aristotle, who developed his ethical thought in a clear confrontation with Plato and his Idea of the Good, considered το αγαθον as something which can be achieved or attained and το αγαθον as one of its qualified species i. e. the "bonum honestum". But when he turned to the metaphysical consideration of Unmoved Movers he found no help in this way of distinguishing αγαθον and καλον and was obliged to look for another more appropriate one. The solution he hinted at in the end was very near to the Platonic "participation" both in its wording and in its real content.
