All of us, when we engage in relatedness, fall under the gravitational influence of another’s emotional world, at the same time that we are bending his emotional mind with ours. Each relationship is a binary star, a burning flux of exchanged force fields, the deep and ancient influences emanating and felt, felt and emanating.

While genes are pivotal in establishing some aspects of emotionality, experience plays a central role in turning genes on and off. DNA is not the heart’s destiny; the genetic lottery may determine the cards in your deck, but experience deals the hand you can play. Scientists have proven, for example, that good mothering can override a disadvantageous temperament.

Walker Percy wrote that “modern man is estranged from being, from his own being, from the being of other creatures in the world, from transcendent being. He has lost something — what, he does not know; he only knows that he is sick unto death with the loss of it.” The mysterious, absent element is a deep and abiding immersion in communal ties. In all of its varied and protean forms, love is the tether binding our whirling lives.

Our society’s love affair with mechanical devices that respond at a button-touch ill prepares us to deal with the unruly organic mind that dwells within. Anything that does not comply must be broken or poorly designed, people now suppose, including their hearts.

Being well regulated in relatedness is the deeply gratifying state that people seek ceaselessly in romance, religions, and cults; in husbands and wives, pets, softball teams, bowling leagues, and a thousand other features of human life driven by the thirst for sustaining affiliations.

The emotional mind likewise transcends the facile and appealing dualism separating its psychological and biological aspects. Physical mechanisms produce one’s experience of the world. Experience, in turn, remodels the neurons whose chemoelectric messages create consciousness. Selecting one strand of that eternal braid and assigning it primacy is the height of capriciousness.

From birth to death, love is not just the focus of human experience but also the life force of the mind, determining our moods, stabilizing our bodily rhythms, and changing the structure of our brains. The body’s physiology ensures that relationships determine and fix our identities. Love makes us who we are, and who we can become. In these pages, we explain how and why this is so.

Like any other momentous shift in emotion, depression is not an occupation by a foreign army; it is civil insurrection, the subversion of identity's republic from within. A depressed person loses more than energy and appetite — he loses himself and the capacity to make the decisions his former, pre-coup self would have made.

Mutuality has tumbled into undeserved obscurity by the primacy our society places on the art of the deal. The prevailing myth reaching most contemporary ears is this: relationships are 50-50. When one person does a nice thing for the other, he is entitled to an equally pleasing benefit – the sooner, the better, under the terms of this erroneous dictum. The physiology of love is no barter.

People rely on intelligence to solve problems, and they are naturally baffled when comprehension proves impotent to effect emotional change. To the neocortical brain, rich in the power of abstractions, understanding makes all the difference, but it doesn’t count for much in the neural systems that evolved before understanding existed. Ideas bounce like so many peas off the sturdy incomprehension of the limbic and reptilian brains. The dogged implicitness of emotional knowledge, its relentless unreasoning force, prevents logic from granting salvation just as it precludes self-help books from helping. The sheer volume and variety of self-help paraphernalia testify at once to the vastness of the appetite they address and their inability to satisfy it.

a mood is a state of enhanced readiness to experience a certain emotion. Where an emotion is a single note, clearly struck, hanging for a moment in the still air, a mood is the extended, nearly inaudible echo that follows. Consciousness registers a fading level of activation in the emotion circuits faintly or not at all. And so the provocative events of the day may leave us with emotional responsiveness waiting beneath our notice. If a man spills coffee on himself, his annoyance is relatively short-lived — on the order of minutes. After the conscious feeling is gone, residual activity in the anger circuits lingers. He will pass into an irritable mood — a quickness to anger, the only reflection of the waning activity in those circuits.

The limbic connectedness of a working psychotherapy requires uncommon courage. A patient asks to surrender the life he knows and to enter and emotional world he has never seen; he offers himself up to be changed in ways he can't possibly envision. As his assurance of successful transmutation he has only the gossamer of faith. At the journey's end, he will no longer be who he was, and his guide is someone he has every reason to mistrust...only human love keeps this from being the act of two madmen. (190)

A culture wise in love’s ways would understand a relationship’s demand for time. It would teach the difference between in love and loving; it would impart to its members the value of the mutuality on which their lives depend. A culture versed in the workings of emotional life would encourage and promote the activities that sustain health — togetherness with one’s partner and children; homes, families, and communities of connectedness. Such a society would guide its inhabitants to the joy that can be found at the heart of attachment — what Bertrand Russell called “in a mystic miniature, the prefiguring vision of the heaven that saints and poets have imagined.