Wolf connects the ability to suffer with the condition of a ”structural relationship between feeling and wanting“, meaning the ability to experience painful situations and to be able to react to these fendingly in the course of a learning process.

Wolf also introduces the additional criteria of the ability to transfer what has already been learnt and to develop a self-conscience of higher living beings, which constitutes an additional moral need for protection.

Two aspects are central to Wolf’s definition of the ability to suffer: Firstly, the expressive powers of pain of other living beings toward the human being is only an indication of a worthiness of protection; its absence, however, does not necessarily justify that the affected living beings do not feel any pain and it would thus be for members of the moral community to make them subject to damage. Secondly, Wolf’s approach is characterized by the fact that empirical differences concerning the dimension of suffering, which can be experienced by the respective moral subject, in opposition to Arthur Schopenhauer do not justify any moral gradation in the worthiness of protection. A moral subject’s ability to suffer, be it an animal or a human being, can only in rare exceptions be weighed against a higher moral good.