"The object of self-love is expressed in the term self; and every appetite of sense, and every particular affection of the heart, are equally interested or disinterested, because the objects of them all are equally self or somewhat else"

This quote by Joseph Butler is describing the principle of self-love. The term "self" is used to express the item of self-love, and Butler is recommending that all of our senses and feelings are either interested in ourselves or something else. This implies that our senses and emotions can be directed towards ourselves or towards something else. Butler is recommending that we ought to understand our own requirements and desires, which we should also know the requirements and desires of others. He is highlighting the value of self-love, but likewise the importance of considering the requirements of others. Ultimately, Butler is suggesting that we should pursue a balance between self-love and consideration for others.