We have now investigated methodology in ethics, animals' basic moral status, and the issue of equal consideration. In this and the following three chapters, we will explore the mental lives of animals, before returning to ethics. This detour may seem abrupt. Why turn from morals to mind?

REASONS TO EXPLORE THE MENTAL LIFE OF ANIMALS

Confronting the scientific and philosophical issues pertaining to animal mentation is an essential part of taking animals seriously and is best done before pushing further into ethics. This is so for several reasons.

First, exploring animals' mental lives is necessary for determining which animals have basic moral status. As was explained in Chapter 3 (and will be elaborated on in Chapter 8), only beings with interests have moral status, and only sentient beings—who, by definition, have certain mental states (see Chapter 5)—have interests. What exactly are these mental states and which animals have them?

But we want to know more than which animals have moral status. Perhaps (even from an equal-consideration view) there are some morally significant differences among beings with moral status. Thus, we want to know (1) whether there are morally important differences among beings with moral status, and, if so, (2) what factual variables underlie such differences, and, in general, (3) which morally relevant traits particular animals have. As we will see in Chapter 8, to determine all this requires work in value theory.