The “problem of other minds”—knowing that someone else has a mind like yours, and in the case of consciousness, subjective experiences similar to yours—is not too much of a problem when we are referring to humans interacting with each other. Indeed, most of our interactions are with other humans. When playing a game of tennis with your friend, for example, it does not seem absurd to say that both of you are having conscious experiences that are similar in nature, allowing you to consciously experience and engage in the game. Of course, the hyperbolic version of the problem remains: you cannot know with absolute certainty that others have minds like yours. But in general, knowledge of other minds is something we need for survival, and children become experts at detecting the intentions and mental sates of others at an early age (with research suggesting that this ability emerges in the first year of life). The non-hyperbolic version of the problem of other minds is actually very easy to solve, and humans are, for the most part, very reliable at solving it.

What about animals? Can we agree on reliable behavioral markers of consciousness? This is a much more intricate question. A good way of approaching this question is to focus on how we attend to the mental states of other human beings when we communicate, and then compare these socially driven kinds of with how animals communicate (we talk more about this below). When evolution is also taken into consideration—given that we have a very good understanding of our genetic lineage—evidence on social skills, attention, and evolution present a strong case for animal mental states. The critical question is whether or not animal mental states are conscious. This question cannot be given a simple “yes or no” answer. Some animals must be more conscious than others, and some may even have experiences similar to ours.

In any case, hyperbolic skepticism about other minds should not stop us from asking such questions. There are good reasons to investigate animal consciousness based on considerations about social attention and communication, as well as evolution. Both philosophers and scientists have taken this route of open inquiry. In fact, three recent books by philosophers focus entirely on the topic of animal consciousness and the evolution of consciousness (Dennett, 2017; Godfrey-Smith, 2016; Tye, 2017). These books provide important insights about animal consciousness. They all favor the kind of graded view mentioned before, according to which not all animals are equally conscious. Some are more liberal than others—Tye says bees and even robots could be conscious, while Godfrey-Smith proposes that insects might not have conscious experiences. Dennett focuses more on and how competence and comprehension are separate things.

To contribute to this debate, we argue that an examination of the distinction between phenomenal consciousness and attention can help clarify some of these issues. For instance, Dennett’s proposals on the evolution of intelligence could be understood in terms of attention routines that do not necessitate phenomenal consciousness, and the question would then be: what else should we be looking at, besides optimal , in order to identify phenomenal consciousness in animals? Godfrey-Smith appeals to the presence of social and skills as a marker. We believe this is in the right direction, and this is why we think that in the evolution of attention only those forms of attention that are empathically oriented towards oneself and others through experience, count as phenomenally conscious. This means that robots are not very likely to become conscious (see Haladjian and Montemayor, 2016). The “why” of phenomenal consciousness is best understood in terms of empathic engagement through basic emotions—such as pain, hunger, or —rather than intelligent decision-making or responses to stimuli, which do not necessitate awareness (see Montemayor and Haladjian, 2015). How should this be investigated?

Source: By Shanthanu Bhardwaj (Dragonfly Uploaded by ComputerHotline) [CC BY-SA 2.0], via Wikimedia Commons

Let’s take insects, for example. Their brains must support some form of representations that allow them to navigate through . Dragonflies have a sophisticated form of selective attention and can keep track of prey while flying through swarms of other dragonflies, enabling them to eat the right things (Wiederman & O'Carroll, 2013). This kind of attention can be very basic and occur without any conscious awareness, throughout all species (as we have been arguing in our previous blog posts, for example, this post on evolution). Bees, for instance, are social creatures but they seem to lack the kind of empathic understanding of each other that cephalopods seem to have—which Godfrey-Smith says are phenomenally conscious.

This between attention and consciousness is a result of evolution, with attention appearing very early (before phenomenal consciousness) to support abilities like tracking targets and navigating through environments. A more focused, voluntary attention is likely to have evolved later as organisms were required to adapt and respond to more complex representations related to forms of learning, tool usage, and (crucially) social interactions such as communicating and maintaining social order within groups. These higher-level cognitive processes require a voluntary, sustained form of attention, as well as interactions with other cognitive processes, such as working memory and . And higher up the complexity ladder, having a conscious self-awareness seems to be a more complex attribute of voluntary attention than mere sustained attention. Self-awareness involves reflecting on the contents of what is being attended and, fundamentally, on one’s own conscious perspective—one is not only aware of these contents, but also aware that one is thinking about them.

Animals clearly exhibit basic forms of attention, enabling them to search for food or avoid predators or navigate through complex environments. Some animals even exhibit higher-level behaviors, such as blue jays, crows, parrots, macaque monkeys, and chimpanzees, by being able to manipulate tools or even possess a very rudimentary language (Griffin & Speck, 2004). And we know that many animals display intelligence, particularly our (see this New York Times article).

Source: John Gerrard Keulemans [Public domain], via Wikimedia Commons

Whether or not animals possess a conscious self-awareness remains debatable, but some have proposed ways in which basic consciousness might be identified in animals (see Edelman, et al., 2005; Griffin & Speck, 2004; Seth, Baars, & Edelman, 2005; Seth, Dienes, Cleeremans, Overgaard, & Pessoa, 2008). For example, Bayne’s (2007) theory of “creature consciousness” specifies that phenomenal consciousness in an organism requires some type of mechanism that generates the “phenomenal field” (possibly related to activity in the thalamus) along with inputs from the different cortical areas responsible for processing sensory and memory-related information. This information must be integrated in some way and only after these integrative processes occur can consciousness be considered present. Clearly, such claims require empirical support and some scientists are beginning to address this issue. Currently, problem-solving behaviors (e.g., tool usage) in animals provide the best examples of the possible presence of cross-modal attention and access to integrated information in animals (for a review on animal consciousness, see Griffin & Speck, 2004). But even here, a further problem we face is determining whether or not this is phenomenally conscious behavior.

Perhaps we can mark consciousness simply by the increasing sophistication of cognitive organization and functions (as argued by Nichols & Grantham, 2000). Even if one thinks that cognitive function could explain the emergence of consciousness, attention and consciousness would still be dissociated since the lower-level forms of attention have evolved in organisms that do not seem to have conscious awareness (see Griffin & Speck, 2004). This is not to deny that there may be phenomenal consciousness in animals—some animals with central nervous systems may experience pain or color in ways that resemble human experiences. But this kind of consciousness is unlikely to be as rich as human consciousness.

Perhaps we can mark consciousness by the ability of a species to cooperate in sophisticated and flexible ways. This is the approach we favor. Understanding the feelings of others through our own emotions may be the reason that consciousness arose—to allow social interactions based on empathy that must be in place for the emergence of a sophisticated that led to the human society we experience today. These are questions to which we still lack a good answer. We believe that carefully examining the consciousness-attention dissociation (or CAD) is a useful approach to distinguish the evolution of two different capacities: capacities to respond optimally to the environment and capacities to have subjective experiences.

Identifying consciousness in animals is certainly a challenge and a compelling topic in many academic and popular discussions (see this article in Aeon). We will never know “what it is like to be a bat” (referring to Nagel’s question) and communication with other species is rudimentary at best (and difficult to separate from simple behavioral responses to a specific stimulus like a pointing finger, see van Rooijen, 2010). While there must be some form of mental activity in animals that serves as the basis for consciousness in humans, it has not yet been identified clearly. Studying how attention and consciousness are related in humans might be the best way to understand what sort of conscious experience is present in animals, while also helping us to better understand human consciousness.

- Carlos Montemayor & Harry Haladjian