Forget ‘I think therefore I am’. In a new theory of embodied consciousness, the neuroscientists Antonio Damasio and Hanna Damasio propose that feelings are the source of consciousness. Long dismissed as secondary to reason, feelings are where consciousness begins. Without them, consciousness is impossible, they argue – with radical implications for the ‘hard problem’ of consciousness and the future of AI.
Please pause for a moment and notice what you are feeling now. Perhaps you notice a growing snarl of hunger in your stomach or a hum of stress in your chest. Perhaps you have a feeling of ease and expansiveness, or the tingling anticipation of a pleasure soon to come. Or perhaps you simply have a sense that you exist. Hunger and thirst, pain, pleasure and distress, along with the unadorned but relentless feelings of existence, are all examples of ‘homeostatic feelings’. Homeostatic feelings are, we argue here, the source of consciousness.
In effect, feelings are the mental translation of processes occurring in your body as it strives to balance its many systems, achieve homeostasis, and keep you alive. In a conventional sense feelings are part of the mind and yet they offer something extra to the mental processes. Feelings carry spontaneously conscious knowledge concerning the current state of the organism as a result of which you can act to save your life, such as when you respond to pain or thirst appropriately. The continued presence of feelings provides a continued perspective over the ongoing body processes; the presence of feelings lets the mind experience the life process along with other contents present in your mind, namely, the relentless perceptions that collect knowledge about the world along with reasonings, calculations, moral judgments, and the translation of all these contents in language form. By providing the mind with a ‘felt point of view’, feelings generate an ‘experiencer’, usually known as a self. The great mystery of consciousness in fact is the mystery behind the biological construction of this experiencer-self.
In sum, we propose that consciousness is the result of the continued presence of homeostatic feelings. We continuously experience feelings of one kind or another, and feelings naturally tell each of us, automatically, not only that we exist but that we exist in a physical body, vulnerable to discomfort yet open to countless pleasures as well. Feelings such as pain or pleasure provide you with consciousness, directly; they provide transparent knowledge about you. They tell you, in no uncertain terms, that you exist and where you exist, and point to what you need to do to continue existing – for example, treating pain or taking advantage of the well-being that came your way. Feelings illuminate all the other contents of mind with the light of consciousness, both the plain events and the sublime ideas. Thanks to feelings, consciousness fuses the body and mind processes and gives our selves a home inside that partnership.
Feelings carry spontaneously conscious knowledge concerning the current state of the organism as a result of which you can act to save your life
That consciousness should come ‘down’ to feelings may surprise those who have been led to associate consciousness with the lofty top of the physiological heap. Feelings have been considered inferior to reason for so long that the idea that they are not only the noble beginning of sentient life but an important governor of life’s proceedings may be difficult to accept. Still, feelings and the consciousness they beget are largely about the simple but essential beginnings of sentient life, a life that is not merely lived but knows that it is being lived.
But how do we know? Thanks to ‘interoception’, the hidden sense that allows us to glean, via bodily feelings, a picture of our interior. It is the important and commonly overlooked department of our organisms charged with both sensing the process of life regulation and adjusting it as needed for life to continue. Exteroception, which includes vision, hearing, touch, taste and smell and is charged with bringing into our minds the entire world that surrounds us, tends to dominate the world of the senses. Proprioception, the sense which allow us to become aware of our bodies in space, and of the movement of our muscles, bones and joints, attracts plenty of attention as well. But interoception is the seemingly modest but real magician, hiding in plain sight.
The machinery of interoception is less sophisticated than that of exteroception and proprioception. It is made of simpler neurons that are often devoid of myelin, assembled in central nervous system structures that are often not protected by a blood-brain barrier, and make use of chemical molecules such as dopamine and serotonin whose chemical actions are slow by comparison with the lightning speed of glutamate or GABA, two of the molecules used by the modern systems that help us perceive the outside world. The good side of all this simplicity is, of course, the intimate contact that interoception allows between the neural elements and the non-neural flesh, a contact so close, in fact, that the two partners, both entirely inside the body, seem to fuse with each other to produce the most intimate of feelings: the feeling of life itself.
This simplicity is indicative of how evolutionarily ancient interoceptive processes are: their neurons and centers show their age, and their chemical molecules are old-fashioned. This is why we propose that feelings produced by interoception were foundational to consciousness and changed the destiny of evolution by allowing the deliberate governance of life.
Are other living organisms conscious or is consciousness an exclusively human feature? Actually, consciousness is ubiquitous in the world of the living. We would say that plenty of non-human organisms are conscious, provided they have the biological machinery that we have just described for humans. But is consciousness present in single-cell organisms? And what about plants? We venture to say that they are not conscious. They ‘sense and detect’ conditions in their surroundings, for example – they run their lives intelligently – but they do not know that they do so. The reason why they do not is that they lack a nervous system. The nervous system is a critical participant in the life process, at once an attentive spectator and an active partner, helping regulate life and generate feelings and the consciousness consequent to them.
Are artificial intelligent devices conscious in some way? Not at all! Even the smart chatbots that are currently attracting so much attention lack any sign of consciousness of the kind that we have just described in living creatures. Once again, consciousness is about feelings and feelings are about life; about the struggle to maintain a program of exchanges with the surrounding environment within certain parameters. None of this applies to current AI devices. They are truly artificial. Access to all the knowledge in the world, and to all the smart devices that may help manipulate that knowledge, cannot produce feelings and consciousness.
Feelings produced by interoception were foundational to consciousness and changed the destiny of evolution by allowing the deliberate governance of life
Where does all of this leave us with regard to the by-now classic ‘hard problem of consciousness’? The hard problem concerns the difficulty of having a physical entity, such as the brain, produce a non-physical process called the mind and, most importantly, a mind whose contents can be experienced, that is, made subjective. Our account of consciousness addresses the hard problem and proposes a candidate mechanism to account for conscious experiences. Time will tell if our solution is correct.