1993) [R]eason may not be as pure as most of us think it is or wish it were [...] emotions and feelings may not be intruders in the bastion of reason at all: they may be enmeshed in its networks, for worse and for better. The strategies of human reason probably did not develop, in either evolution or any single individual, without the guiding force of the mechanisms of biological regulation, of which emotions and feeling are notable expressions. Moreover, even after reasoning strategies become established in the formative years, their effective deployment probably depends, to a considerable extent, on a continued ability to experience feelings.

This is not to deny that emotions and feelings can cause havoc in the processes of reasoning under certain circumstances. Traditional wisdom has told us that they can, and recent investigations of the normal human reasoning process also reveal the potentially harmful influence of emotional biases. It is thus even more surprising and novel that the absence of emotion and feeling is no less damaging, no less capable of of compromising the rationality that makes us distinctly human and allows us to decide in consonance with a sense of personal future, social convention, and moral principle.

Nor is this to say that when feelings have a positive action they do the deciding for us; or that we are not rational beings. I suggest only that certain aspects of the process of emotion and feeling are indispensable for rationality. At their best, feelings point us in the proper direction, take us to the appropriate place in a decision-making space, where we may put the instruments of logic to good use. We are faced by uncertainty when we have to make a moral judgment, decide on the course of a personal relationship, choose some means to prevent being penniless in old age, or plan for the life that lies ahead. Emotion and felling, along with the covert physiological machinery underlying them, assists us with the daunting task of predicting an uncertain future and planning our actions accordingly. [...]

There has never been any doubt that under certain circumstances, emotion disrupts reasoning. The evidence is abundant and constitutes the source for the sound advice with which we have been brought up. Keep a cool head, hold emotions at bay! Do not let your passions interfere with your judgment. As a result, we usually conceive of emotion as a supernumerary mental faculty, an unsolicited, nature-ordained accompaniment to our rational thinking. If emotion is pleasurable, we enjoy it as a luxury; if it is painful, we suffer it as an unwelcome intrusion. In either case, the sage will advise us, we should experience emotion and feeling in only judicious amounts. We should be reasonable.

There is much wisdom in this widely held belief, and I will not deny that uncontrollable or misdirected emotion can be a major source of irrational behavior. Nor will I deny that seemingly normal reason by be disturbed but subtle biases rooted in emotion. [...] Nonetheless, what the traditional account leaves out is a notion that emerged from the study of patients [with frontal lobe damage who are incapable of emotional responses] [...]: Reduction in emotions may constitute and equally important source of irrational behavior. The counterintuitive connection between absent emotion and warped behavior may tell us something about the biological machinery of reason.

Antonio R. Damasio
Descartes' Error (1994)

1994) Among animals, from insects to mammals, there are unequivocal examples of successful coping with particular forms of environment on the basis of innate strategies, and no doubt these strategies often include complex aspects of social cognition and behavior, I never cease to marvel at the intricate social organization of our distant monkey cousins, or at the elaborate social observances of so many birds. When we consider our own species, however, and the far more varied and largely unpredictable environments in which we have thrived, it is apparent that we must rely on highly evolved genetically based biological mechanisms, as well as suprainstinctual survival strategies that have developed in society, are transmitted by culture, and require, for their application, consciousness, reasoned deliberation, and willpower. This is why human hunger, desire, and explosive anger do not proceed unchecked toward feeding frenzy, sexual assault, and murder, at least not always, assuming that a healthy human organism has developed in a society in which suprainstinctual survival strategies are actively transmitted and respected. [...]

A task that faces neuroscientists today is to consider the neurobiology supporting adaptive supraregulations, but which I mean the study and understanding of the brain structures required to know about those regulations. I am not attempting to reduce social phenomena to biological phenomena, but rather to discuss the powerful connection between them. It should be clear that although culture and civilization arise from the behavior of biological individuals, the behavior was generated in collectives of individuals interacting in specific environments. Culture and civilization could not have arisen from single individuals and thus cannot be reduced to biological mechanisms and, even less, can they be reduced to a subset of genetic specifications. Their comprehension demands not just general biology and neurobiology but the methodologies of the social sciences as well.

In human societies there are social conventions and ethical rules over and above those that biology already provides. Those additional layers of control shape instinctual behavior so that it can be adapted flexibly to a complex and rapidly changing environment and ensure survival for the individual and for others (especially if they belong to the same species) in circumstances in which a preset response from the natural repertoire would be immediately or eventually counterproductive. The perils preempted by such conventions and rules may be immediate and direct (physical or mental harm), or remote and indirect (future loss, embarrassment). Although such conventions and rules need be transmitted only through education and socialization, from generation to generation, I suspect that the neural representations of the wisdom they embody, and of the means to implement that wisdom, are inextricably linked to the neural representation of innate regulatory biological processes. I see a "trail" connecting the brain that represents one, to the brain that represents the other. Naturally, that trail is made up of connections among neurons. [...]

Does this mean that love, generosity, kindness, compassion, honesty, and other commendable human characteristics are nothing but the result of conscious but selfish, survival-oriented neurobiological regulation? Does this deny the possibility of altruism and negate free will? Does this means that there is no true love, no sincere friendship, no genuine compassion? That is definitely *not* the case. Love is true, friendship sincere, and compassion genuine, if I do not lie about how I feel, if I really feel loving, friendly, and compassionate. Perhaps I would feel more eligible for praise if I arrived as suchsentiments by means of pure intellectual effort and willpower, but what if I have not, what if my current nature helps me get there faster, and be nice and honest without even trying? The truth of the feeling (which concerns how what I do and say matches what I have in mind), the magnitude of the feeling, and the beauty of the feeling, are not endangered by the realizing that survival, brain, and proper education have a lot to do with the reasons why we experience such feelings. The same applies to a considerable extent to altruism and free will. Realizing that there are biological mechanisms behind the most sublime human behavior does not imply a simplistic reduction to the nuts and bolts of neurobiology. In any case, the partial explanation of complexity by something less complex does not signify debasement.

The picture I am drawing for humans is that of an organism that comes to life designed with automatic survival mechanisms, and to which education and acculturation add a set of socially permissible and desirable decision-making strategies that, in turn, enhance survival, remarkably improve the quality of that survival, and serve as a basis for constructing a person. At birth, the human brain comes to development endowed with drives and instincts that include not just a physiological kit to regulate metabolism but, in addition, basic devices to cope with social cognition and behavior. It emerges from child development with additional layers of survival strategy. The neurophysiological base of those added strategies is interwoven with that of the instinctual repertoire, and not only modifies its use but extends its reach. The neural mechanisms supporting the suprainstinctual repertoire may be similar in their overall formal design to those governing biological drives, and may be constrained by them. Yet they require the intervention of society to become whatever they become, and thus are related as much to a given culture as to general neurobiology. Moreover, out of that dual constraint, suprainstinctual survival strategies generate something probably unique to humans: a moral point of view that, on occasion, can transcend the interests of the immediate group and even the species.

Antonio R. Damasio
Descartes' Error (1994)