In the present article, we are faced with two phenomenological philosophers who, in two different intellectual traditions, namely philosophical hermeneutics and moral phenomenology, have referred to the concept of the Other as the fundamental possibility of the individual. The other, as an ontological and common concept in the thought of Gadamer and Levinas, is the turning point of the condition for the possibility of understanding and ethics. Focusing on the concept of the other, while addressing the points of difference and commonality between Gadamer and Levinas, this article will show that Levinas’s preoccupation with the other as a philosopher refers to the foundations of ethics, and the condition for the possibility of foundations of ethics is encountering the other. In Gadamer, the turning point is the determination of the possibilities of understanding in dialectical and dialogue-oriented relationships. Without the other, in Levinas’s thought, ethics, and moral matter, and in Gadamer’s thought, the process of understanding will not occur in the form of a fusion of horizons. Therefore, this article shows that the other is a common concept between these two philosophers, which both of them cannot avoid in their philosophical analyses of ethics or the process of understanding.