Are animals phenomenally conscious? You won’t find a categorical ‘yes’ to this question in Peter Carruthers’ new book. You won’t find a categorical ‘no’ either. You will find instead a case in favor of the thesis that there is no fact of the matter concerning phenomenal consciousness in animals. There is just no empirical way to decide this question. Thus, arguing in favor or against the actual existence of animals who are phenomenally conscious does not have any scientific relevance.

Phenomenal consciousness is a kind of consciousness with a distinctive subjective feel. A subject is said to be phenomenally conscious if she has undergoing mental states such as seeing a red ripe tomato or smelling a bunch of burning hairs. Phenomenal consciousness is exclusively nonconceptual in nature and does not admit degrees. Since the what-it-is-like feel proper to phenomenal consciousness is given through introspection, a subject is either phenomenally conscious or not. There is no halfway. It is an all-or-nothing issue.

Typically, philosophical writings refer to the properties of phenomenal consciousness by means of the term ‘qualia’ (plural noun of ‘quale’). A thought-experiment popularized in the 1990’s by David Chalmers suggests that it is possible to conceive entities that have physical properties and functional representations but lack qualia. In other words, zombies are conceivable. The logical corollary is that qualia are irreducible to physical properties and functional representations. This explanatory gap is known as the “hard problem of consciousness.” Such a problem and its underlying qualia realism (the world comprising physical properties and qualia) are inextricably associated to the debate about phenomenal consciousness. Carruthers’ book aims to put this debate and the hard problem of consciousness laid to rest.

Our author defends and elaborates the view that the human mind is fully continuous with the minds of animals. This does not entail that animals are phenomenally conscious, however. Carruthers addresses this matter within the frame of a specific theory of consciousness: the global-workspace theory. As presented, the theory is said to explain satisfactorily the conscious/unconscious distinction as well as to explain away the hard problem of consciousness. It argues that conscious states are those that are globally broadcast to systems for reporting, planning, remembering, and so on. That is why subjects are aware of them. Unconscious states are those that are not so broadcast – that is why subjects are not aware of them! Phenomenal consciousness, on the other hand, comprises globally broadcast nonconceptual content. The nature of this phenomenon is explained by the global-workspace theory as it shows how it is possible for humans to have higher order thoughts lacking conceptual connections with physical, functional or representational facts about nonconceptual content. For Carruthers, this evidences that a naturalistic explanation for all the facts involved in consciousness is possible. If so, the hard problem of consciousness vanishes and there are no qualia.

The global-workspace theory points out that there is no fact of the matter whether animals are phenomenally conscious or not. Because, among other reasons, the concept of phenomenal consciousness is a first-person one, and as such it cannot be applied liberally to minds different from those of humans. Additionally, we are not justified to apply this concept – which is all-or-nothing and does not admit degree – to animal minds since they resemble the human global workspace just to some degree. Asserting that there is no fact of the matter concerning phenomenal consciousness in animals does not make of Carruthers an agnostic about any kind of consciousness in animals. Obviously, he cannot deny that animals are conscious of objects and events in their environment (transitive consciousness). Nor he can deny that animals are often awake rather than unconscious (intransitive consciousness). His enterprise is restricted to show that it is not possible to project the concept of phenomenal consciousness (the what-it-is-like feels) from the minds of humans into the minds of animals save in case of stipulation. No doubt, animal minds and their problems should be further studied, but phenomenal consciousness not. (Animal ethicists do not need to feel disturbed by this book. It does not offer reasons against the moral consideration of animals. In Carruthers’ view, sympathy (not empathy) for animal suffering can still be appropriate.)

Ironically, we are presented with a book whose well-structured chapters offer a series of complex conceptual analyses and empirically-informed arguments about different aspects of consciousness in humans and animals just to recommend readers that “they should stop thinking about consciousness and start investing their time in more important things.” It is a worthy and enlightening reading, though.

David Villena, Department of Philosophy, Lingnan University, Hong Kong.

Categories: Philosophical

Keywords: philosophy of mind, animal minds