When Darwin wrote the Origin of Species (1859, 424), he famously closed the book with the provocative promise that, “[L]ight will be thrown on the origin of man and his history.” In his Descent of Man (1871) and his Expression of Emotions in Man and Animals (1872), Darwin began to throw some of that promised light, especially regarding the emotional and cognitive similarities (homologies) of mammals. But shortly after this beacon, all went dark again. The rise of positivism in the early twentieth-century, paired with the turn toward genetics, and the ascent of behaviorism effectively lowered the curtain on biological speculations about the evolution of the mind.
When researchers finally turned again to the mind in the mid-twentieth century, it was the computer that both sparked the cognitive sciences revolution and served as its exclusive investigative tool. Yet for all the successes of machine learning (and they are impressive), our understanding of biological minds seems to have gotten lost in the shuffle. While algorithmic digital computation produces problem-solving machines, such problem solving—confusedly called “intelligence” by the dominant paradigm—lacks the obvious motivational goads and other affective triggers observed in real sentient animals. Even traditional evolutionary psychology (which should have been biologically oriented) gained popularity in the 1990s by actually ignoring the evolved nature of the brain and body, in favor of postulated computational modules, to explain human behavior in some largely mythical Pleistocene. Indeed, contemporary moral psychology and its philosophical counterpart often continue this modular approach, assuming the existence of innate normative switches in the human mind and discounting the emotional nature of ethical actions.
With much less fanfare, the late 1990s saw the recognition of an affective science, especially in the pioneering work of Jaak Panksepp, Antonio Damasio, and Richard Davidson. The field of affective neuroscience isolates emotional brain systems (largely in the regions of the brain that we share with other mammals) that undergird adaptive behaviors in vertebrates. With the help of neuroscientific and behavioral research, we are beginning to appreciate how the ancestral mammal brain is alive and well inside our higher neocortical systems. Unlike the computational approach to mind, the affective turn is deeply rooted in what we know about the brain as a biological reality. In the first decade of the new millennium, affective (or emotional) studies began to trickle into disciplines like ethology (e.g., Frans De Waal), economics (e.g., Daniel Kahneman), clinical practice (e.g., Jonathan Rottenberg and Mark Solms), and philosophy (e.g., Martha Nussbaum). But the time has finally come for a full-scale exploration of the evolution of emotions and mind in the biologically-rooted human being.
THE AFFECTIVE ROOTS OF MIND
In our new book, The Emotional Mind: The Affective Roots of Culture and Cognition (2019), we argue that emotional systems are central to understanding the evolution of the human mind (as well as those of our primate cousins). We bring together insights and data from philosophy, biology, and psychology to shape a new research program.
For at least 200 million years, the emotional brain has been under construction. By comparison—the focus of the cognitive approach—the expansion of the “rational” neocortex around 1.8 million years ago is a latecomer on the scene, and the development of our language symbol system is younger still. As a suite of adaptive tools, the emotions have been at work substantially longer than rational cognition, so it makes little biological sense to think about the mind as an idealized, rational, cost-benefit computer projected into deep time.
A sufficient account of the evolution of mind has to engage more than only the power of propositional thinking that is exemplified in our rarefied ability to manipulate linguistic representations. We will have to understand a much older capacity—the power to feel and respond appropriately. We need to analyze the evolution of mind in terms of layers of consciousness, i.e., the interaction between specifiable sets of functional systems. At the lower layers we have basic drives that prod us (and other animals) out into the environment for the exploitation of
resources. Thirst, lust, fear, and so on are triggers in evolutionarily earlier regions of the brain that stimulate vertebrates toward satisfaction and the return to homeostasis (physiological balance).
At the lowest primary level, fear, for example, is radical. Under threat, the fearful animal voids its bowels and a surge of activity in the amygdala and hypothalamus readies it for defense or escape. The brain of mammals creates a feedback loop between these ancient affective systems and the next layer up: that which is responsible for the experiential learning and conditioning that a creature undergoes. At this secondary level, fear (to continue our example) becomes more specific: rats are afraid of light, while humans are afraid of the dark. Same fear system, different threats. And, finally, another feedback loop exists between the neocortical “rational” cognitive processes and the aforementioned subcortical triggers and learning systems. At this top level, the tertiary level, fear is enmeshed with higher level conceptual and narrative thinking, producing the possibility for a culturally mediated experience, such as horror.
Ruminations and thoughts—underwritten by language, symbols, executive control, and future planning—constitute this tertiary-level, though they are energized by the lower level emotion. At this third level, we arrive at uniquely human emotions, like those elaborate and ephemeral feelings so beautifully articulated by introspective literary savants, such as Henry James, Fyodor Dostoyevsky, and Edgar Allan Poe, in the case of horror. Tertiary affect and neocortical awareness have cognitive executive functions, such as the reflective intention to act (which is associated with the prefrontal cortex), rumination, and emotional regulation (which is associated with the medial frontal cortex) (Panksepp 1998).
There are bottom-up causes of mind (i.e., those that push the organism to satisfy specific physiochemical requirements), but also top-down causes (i.e., those that regulate limbic experiences through neocortical cognitive and behavioral strategies) (Panksepp 2011). Conscious subjectivity does not suddenly arise at the top arc of this feedback circle, rather it exists throughout creatures of the mammalian clade as a foundational motivation process that is related to biological homeostatic triggers. Emotions in primary and secondary layers are sometimes thought of as “unconscious,” and even when we are regulating them, we do not have clear introspective conscious access to their functioning (Winkielman and Berridge 2001). It is thus more accurate to say that primary and secondary emotions have phenomenal consciousness (experiential feeling), but lack access consciousness (the ability to rationally access, manipulate, and reflect upon emotions) (Block 2007).
Following our late mentor Jaak Panksepp (1943-2017), we think all mammals share seven foundational affective systems: FEAR, LUST, CARE, PLAY, RAGE, SEEKING, and PANIC/GRIEF. Each of these has specific neural electrochemical pathways, with accompanying feeling states and behavior patterns. Other researchers draw the map slightly differently regarding what counts as a “primary emotion,” but affective science should be able to iron out the best taxonomy in the decades to come. These seven emotions are universal in humans (and mammals), but they are filtered through the three layers of the emotional mind, creating tremendous diversity.
The biological and psychological sciences have historically isolated or focused on one layer of mind to the exclusion of others, and thereby presented partial and sometimes conflicting pictures of mind and behavior. Many computationally oriented cognitive scientists tend to focus on tertiary-level processing, while behaviorists focus on secondary-level processing.
We think the lowest layers of mind permeate, infiltrate, and animate the higher layers. The evolution of mind is the developmental story of how these layers emerged and acted as feedback loops on each other. Such feedback, however, does not exclusively take place in the brain, rather it is embedded in embodied, enactive, and socio-cultural processes. The impressive achievements of a human cognitive niche are often heralded, but the
emotional niche has gone unsung. We argue that the advances of complex tool industry, for example, or the evolution of family structures could not have happened without parallel advances in Homo emotional life.
An affective or emotional approach can demonstrate the surprising relevance of feelings to perception, thinking, decision-making, and social behavior. The mind is saturated with feelings. Almost every perception and thought has valence, or is emotionally weighted with some attraction or repulsion quality. Moreover, those feelings, sculpted in the encounter between neuroplasticity and ecological setting, provide the true semantic contours of mind. Meaning is foundationally a product of embodiment, our relation to the immediate environment, and the emotional cues of social interaction, not abstract correspondence between sign and referent. The challenge then is to unpack this embodiment. How do emotions like care, rage, lust, and even playfulness create a successful social world for mammals, an information-rich niche for human learning, and a system for ideational salience? Our book strives to provide a conceptual roadmap to answer that question.
The first chapter explains the motivation for our project by delineating how the study of affect clarifies lacunae in models of mind provided by behaviorism and cognitive science. The second chapter charts our ontological positions with an emphasis upon key issues in the philosophy of biology, including teleology, intentionality, determinism, causality, and developmental processes. Our debt to Aristotle and Spinoza reveals our deeper ontological position. Spinoza saw nature in fairly mechanical deterministic terms, but he recognized that living things share a simple goal-oriented tendency: they strive to survive. He called this animation principle of living systems “conatus” (striving), and considered it the very essence of all biological creatures. It is nothing like the teleology of the natural theologians, but rather a recognition that nature has an essential goal-directed imperative within it that cannot be captured by purely billiard-ball causation. Biological systems are themselves intentional.
Equipped with conatus, proto-representational abilities, and homeostatic processes, creatures pursue “maximum grip” on their environments. Conative aboutness in homeodynamic systems is a kind of intentionality prior to decoupled representations; this line of thinking is a neglected teleological approach. Ecological teleology is an example of mammalian intentionality before the representational mind; indeed, the latter could be derivative of the former. Cartesian and digital notions of mind have failed to incorporate this aspect of embodiment.
We build a model of the evolution of the mind to include the diverse roles of emotion, beginning with an outline of a model of social intelligence and the foundation it provides for the phylogenetic and ontogenetic cultural accumulation of information. Our approach emphasizes the features of mental life that are homologous with non-human primates. Much of our understanding of primate ethology is gained through the work of primatologists Frans de Waal, Craig Stanford, Robert Sapolsky, and Sarah Hrdy. We discuss a set of perceptual, emotional, and social processes as the proximal causes that enable culture and cultural learning as investigated by philosopher Kim Sterelny and psychologist Darcia Narvaez et al. (2013).
Chapter three provides a theoretical model of social processes through considering how affordances transform the scope of perception, nonverbal communication, and the role of emotions therein. Chapter four delivers a phylogenetic story of social intelligence through a comparative analysis of primate social behavior in its ecological and emotional context. Chapter five suggests an ontogenetic narrative of the developmental psychology of social intelligence in the infant-caregiver relationship.
Next, in chapters five through seven we trace affective systems through transformations that enabled representational mental processes, social organization, religion, and art. Our key principle is the notion of de-coupling: when an affective response or a perceptual representation is freed from necessity, and it attaches onto and expands into other functions. Put another way (following philosopher Ruth Millikan), the human mind evolved the ability to separate or disconnect the indicative from the imperative functions of an image, sound, or memory. This provided enough distance from automatic action-responses that representations could be manipulated (i.e., counterfactuals arose), and a “second universe” slowly emerged inside the head of Homo. Most contemporary work on the evolution of mind fails to address the way in which intellectual representations originated in earlier animal abilities. In this section of the book, we articulate an empirically-informed model of how primates transitioned from bodily simulations (the beginnings of decoupling) to symbol systems, and how those eventual symbolic systems still bear the mark of their affective roots.
Finally, in the final chapters (eight and nine), we argue for the role of affect in the relationship between ontogenetics and group level socio-cultural adaptations (and exaptations) in social organization, religion, and art. Under increasing voluntary control, the pictorial and narrative faculty of imagination furnishes a bridge between passive sensual memory and associationism on the one hand, and active adaptive appraisal (or judgment), as well as mimetic cultural codification of survival strategies, on the other hand. We make a series of arguments for the emotionally therapeutic and prosocial aspects of religion, mythology, and art as adaptive functions of creativity. In those rare cases where researchers acknowledge an adaptive natural history of religion, they tend to offer cognitive interpretations (i.e., primitive religion is a crude proto-science that helps early man make predictions about and to understand nature). But this is an incomplete picture, thus we argue that the principal role of religion is to shape social solidarity through ritualized, affective sculpting.
An affective approach to culture also helps us understand some stubborn contemporary confusions. New Atheists, like Richard Dawkins and Dan Dennett, evaluate religion at the neocortical level—their criterion for assessing its claims is the hypothetico-deductive method of verification. However, while religion may fail at the bar of rational validity (explanans), it is the wrong bar for evaluating religion. The limbic brain, built by natural selection for solving survival challenges, was not initially rational. Systems that culturally manage our emotions were selected for because they helped early mammals flourish. William James understood the tension between passional and rational agendas long before we had a neurological way of framing it. James recognized that faith is not knowledge in the strict sense, but since it is deeply meaningful (in the affective domain), it is important to see how and why it might be warranted. He also understood that secular reason is more feeling-laden than we usually admit, that there is a sentiment of rationality that is worth exploring. Our book closes with an argument about how approaching the ethereal issue of faith with an appreciation of the affective roots of an emotional mind will allow for nuanced insight.