If evolution is true (it is), then we should expect to find precursors for human morality in non-human animals. And we have (I told you, evolution is true!): scientists have identified a wide range of supposedly moral behaviors in non-human animals. Yet many people are skeptical of their claims, and argue that humans cannot reasonably infer the motivations that drive non-human animals to act in supposedly moral ways.

But in his new book, Can Animals Be Moral?, University of Miami philosophy professor Mark Rowlands posits that, given our evolutionary link, it’s only reasonable to conclude animals act moral for the same reasons humans do: emotions

We might think of [British ethologist Conwy Lloyd Morgan’s] Canon as akin to a game with a set of arbitrary rules: don’t give animals anything more than you absolutely have to. Assume only the bare minimum of cognitive abilities required to explain their behaviour. Ditto emotional sensibilities. Moral emotions — kindness, sympathy? Certainly don’t give them those unless there is no other choice. We know that we have cognitive and emotional capacities aplenty, and we know that we can, and often do, act for moral reasons. But don’t assume other animals are like us unless there is no other option.

Here, courtesy of [Frans] de Waal, is another possible game. We know that animals are like us in many ways — in terms of their evolution, their genetic structure, the structure of their brains, and their behaviour. Given these known similarities, when we see animals behaving in ways that seem to be similar to the ways we behave, then do not assume a difference in motivation unless there is some evidence that supports this difference. When a chimpanzee gives what appears to be a consoling hug to its fellow who has just received a savage beating from the alpha male then, in the absence of evidence to the contrary, the working hypothesis should be that the chimpanzee is motivated by the same sorts of emotions as a human would be in the same sort of situation. If, in the human case, we take this to be an expression of sympathy, then we should assume the same for the ape unless there is positive evidence to suppose otherwise.

For Rowlands, the debate over these two ways of thinking boils down to whether you accept morality as biological or intellectual in nature. 

The crux of this issue has as much to do with humans as it does with animals. When humans act morally, what is it we are doing? Traditionally, the philosopher’s answer has been an intellectualist one: acting morally requires the ability to think about what we are doing, to evaluate our reasons in the light of moral principles. But there is another tradition, associated with the philosopher David Hume and developed later by Charles Darwin, that understands morality as a far more basic part of our nature — a part of us that is as much animal as it is intellectual. On this ‘sentimentalist’ account of morality, our natural sentiments — the empathy and sympathy we have for those around us — are basic components of our biological nature. Our morality is rooted in our biology rather than our intellect.

If this is true, then the reasons for thinking that animals cannot act morally dissolve before our eyes. What is left is a new understanding of what we are doing when we act morally and, to that extent, the sorts of beings we are. Those beings are, perhaps, just a little more biological and a little less intellectual, a little more animal and a little less spiritual, than we once thought.

I think most scientists and philosophers would agree with Rowlands that morality has a largely biological basis, but they would also argue that intellect plays an important role in honing our sense of morality. I’m not saying Rowlands would discount the significant role of intellect in shaping one’s moral behavior (I haven’t read his book), but I stress this point because it has an important implication: if intellect shapes our moral senses, then you could say humans are motivated to act morally, at least in part, for reasons other than emotional ones — a difference worth serious consideration.