Varieties of Sanity
Mental illness comes in several varieties: schizophrenia, bipolar disorder, depression, anxiety, neurosis, eating disorders, obsessive-compulsive disorder, post-traumatic stress disorder, paranoia, impulse control disorder, tic disorder, sexual disorders. These illnesses can be possessed independently (though there are certain correlations): you can have one without having the others. I take the big three to include psychosis, manic-depression, and lack of impulse control: these are the three main ways in which the mind can assume pathological traits. At any rate, I shall focus on these three in what follows. My question is: Does sanity have a similar structure? Are there different types of sanity? You can be insane in several different ways, but can you be sane in several different ways? And what does this tell us about the nature of sanity and its possible enhancement?
What is sanity? The OED defines it thus: “of sound mind; not mad”. This suggests that the primary concept of the pair sane–insane is the latter: the concept of sanity was introduced by way of contrast with the concept of insanity, of which salient instances had been observed. To be sane is to not have any of the ailments classified as mental illnesses. To be normal is not to be abnormal. Compare the concepts of bodily health and ill health: to be of “sound body” is not to have various bodily ailments. To be healthy is not to be ill. But we can surely do better than this, since there must be traits that constitute sanity, as there are traits that constitute health of the body. To be sane is to have these traits, or to have them in good measure. Compare the traits that constitute bodily fitness (or one aspect of it): strength, endurance, and flexibility. To be unfit is to be weak in these dimensions, but to be fit is to possess them in good measure. So what are the traits variations in which constitute mental health and mental ill health?
We can take our cue from the types of mental illness listed above. The affective instability characteristic of manic-depression suggests that affective evenness is a type of sanity: affective sanity is keeping on an even keel, not being too happy or too sad. As we might say, it is having rational emotions—ones appropriate to objective circumstances. Not being deliriously happy about nothing very much or cast down by the slightest setback. The sane person has good emotional regulation. In the case of psychosis (schizophrenia) the natural thought is that it is the hallucinations and delusions of the psychotic that qualify him as mad; so the sane person is one who is notdeluded or hallucinated. More precisely, it is someone who is free of delusion in good measure (everyone might be a bit deluded—as in romantic love). I shall say simply that cognitive sanity consists in being non-delusional in one’s beliefs—being a good curator of one’s beliefs. Not being subject to fantasy beliefs or delusions of persecution or under the impression that one is the messiah. It is being “sound of intellect” (as distinct from affect). Third, a person with impulse control problems cannot help acting in ways that may not be in his or her best interests (or the interests of others): blurting things out, reaching repeatedly for the cookie jar, obsessively washing your hands, hitting the cat for no reason. Then being sane in respect of impulse control is simply acting with restraint—sensibly, prudently, moderately, and maturely. It is not acting on any passing whim or harmful urge. This is to be sound of will (as distinct from affectively or intellectually): having a well regulated will. Here it is action that can be pathological not emotion or thought. It is what the agent does, not what he thinks or feels that makes him fall into the category of the mentally ill.
So we have three aspects of the mind—emotion, thought, and will—that can vary in certain ways, and these ways determine whether the person is sane or insane, mentally well or ill. Let us then say, for the sake of brevity, that sanity consists in evenness, truthfulness,  and self-control. These are the virtues proper to emotion, thought and will (to put it in Aristotelian terms); and sanity consists in possessing these virtues while insanity consists in lacking them (or not having them in good measure). So now we can return to our original question and answer as follows: there are three types of sanity, which can in principle be possessed independently of each other—sanity of emotion, sanity of thought, and sanity of action. Affective sanity is evenness of emotion; cognitive sanity is truthfulness of belief; and conative sanity is restraint in action. You may be strong in one area but not in the other two (as you may be physically strong but not flexible or have much endurance): you might, say, be generally truthful in your beliefs but prone to emotional instability or impulsive actions; or you might be cautious in action but prone to depression; or you might be emotionally even but deluded and impulsive. No doubt there are correlations between the components of sanity, as there are for the types of mental illness, but we can discern three distinct dimensions of sanity—three sorts of mental wellness. So sanity is not just a unified blank state of not having various mental ailments; it is a positive composite state made up of discrete components (it has “modularity”). Strictly speaking, we should not describe a person as sane without being prepared to specify what type of sanity we are talking about—just as we must not describe a person as insane without being able to specify what type of insanity we have in mind. For the sake of linguistic accuracy, we might speak of emotional sanity, cognitive sanity, and active sanity (“Oh yes, he is quite sane cognitively but pretty crazy actively”).
I have not taken a stand on whether sanity and insanity differ merely by degree, though clearly there are degrees of evenness, truthfulness, and restraint. The point is that just as insanity has varieties so too does sanity: mental wellness is modular in roughly the way mental illness is. The psychological faculties can be independently subject to breakdown or disease, but they can also be differently developed in different individuals (or the same individual at different times). For it is not true that any deficiency in a psychological faculty constitutes a mental illness. I may be less physically strong than you, but that doesn’t mean I am physically ill; and I may be less fleet of thought than you, but that also doesn’t mean I am mentally ill. Sanity can vary both in type and in degree of excellence. I might be perfectly well in all three departments but still striving for improvement—I want to be even saner than I already am. So we need to distinguish psychotherapy (or psychiatry) from what might be called “sanity training”: the former aims to rectify mental illness while the latter aims to promote mental wellbeing to yet higher levels of excellence. The distinction mirrors the distinction between physiotherapy and athletic training: fixing injuries versus improving performance. You can work on your strength, flexibility, and endurance; and you can work on your evenness, truthfulness, and restraint—without any suggestion that you are ill. There are three things to work on in each case, corresponding to the three faculties that admit of breakdown or improvement. The varieties of mental wellness correspond to varieties of mental training method—ways to enhance or improve sanity (not merely cure insanity).
I am suggesting that we tend not to think of sanity in a sufficiently structured way—as we used not to think of insanity in a sufficiently structured way. It wasn’t till the nineteenth century that we started to recognize the varieties of mental illness, relying instead on some undifferentiated notion of “mental fugue” or perturbation of the “animal spirits” (or a grievous moral failing); similarly, today we tend to think of the sound mind in an undifferentiated way, as if it is just one kind of seamless thing. Hence we have the simplistic binary opposition of sane and insane, with sanity as just the negation of its opposite. Our habitual concepts are too crude to capture the psychological reality: sanity is a multifaceted thing not just a uniform state of overall mental wellbeing. I am not denying that a certain kind of holism might characterize mental wellness, according to which all three types of wellness presuppose the others; but that doesn’t defeat the thesis that there are three types of mental wellness—just as holism about meaning or belief doesn’t imply that there are no such things as separate meanings or beliefs. The ancients tended to think that Reason alone could ensure mental health, so that cognitive sanity would bring with it affective and conative sanity; that seems unduly optimistic (and not consistent with the facts of mental illness), but in any case it is acknowledged that there are three areas of wellness to consider. They are certainly conceptually distinct, and apparently distinct in psychological realization. No doubt the brain areas responsible for each faculty are distinct, as are their biological pathologies. In principle, a virus could target one area and not the others, thus producing radical dissociation of mental functioning—insane in one way but not in others. Just consider phobias: it is certainly possible to have a phobia with respect to one sort of stimulus but not with respect to others—“insane” in one way but not in other ways. There is no such thing as a generalized phobia, merely specific types of phobia. Phobias are highly modular.
What is the cause of sanity? The question is not unreasonable. We can ask what the cause of insanity is—organic damage, the genes, parental upbringing, excessive studying—so why can’t we ask what the cause of sanity is? Or better, to reflect the complexity of sanity, what the causes are: what leads to sanity (or greater sanity) in the three areas mentioned? Once we have a clearer idea of causes we can pursue methods of treatment or training. Suppose cognitive sanity is caused by a rigorous training in mathematics (the Platonic theory of sanity): then that is how we should train our young in order to produce high levels of sanity. If emotional evenness is caused by proper parental praise and blame, then that is what we should emphasize in producing it. If impulse control is caused by meditation, then meditate away. All over the world we now have centers for combatting psychological ill health, but why not invest in centers that promote good mental health? Just as we have gyms as well as hospitals for aiding physical health, why not have places you go to in order to work on your mental health? You might do a workout devoted to emotional stability one day and then on another day work on your truthfulness or your impulse control. You might want to get really good at all three! I don’t have any specific suggestions for exercise routines, but the idea is not intrinsically absurd. One possibility that suggests itself is to use dramatic enactments in order to develop your level of sanity: you act out various scenarios that test your ability to be even, truthful, and restrained. My point is that this is the kind of thing that suggests itself once we have become attuned to the varieties of sanity–and to the fact that sanity is a positive achievement not merely the absence of insanity. We might even say that it is a skill—a talent that can be nurtured and improved upon. You could undertake to become saner every day, to pay attention to your level of sanity, and not take it for granted (especially when it has been challenged by events in your life).  Sanity is something to be prized and enhanced, not simply assumed and left to its own devices. I wouldn’t be opposed to weekly sanity classes in school to supplement the usual student counselor. Sanity coach seems like a worthwhile occupation (the educational requirements would have to be stringent, however).
 I am using this word in an extended sense to include not only sincerity in speech but also accuracy in thought. It is odd that we have no natural word for this property, the property of having a propensity to form true beliefs. Some people are better than others at forming true beliefs, and the psychotically insane are particularly bad at it; truthfulness in this sense is critical to cognitive sanity. Someone who forms his beliefs by following his fantasies is not a sane person. (The question of what it takes to be a good curator of one’s beliefs is a complex one.)
 The idea of psychological wounds strikes me as real and important: these can cause states of insanity, or borderline insanity, or at least emotional trauma, and they need to be properly treated. Just as the body needs to be rehabilitated after injury, so does the psyche; and the injury might be selective and specific, requiring a specially designed kind of treatment. Mental health needs to be preserved in the face of such wounds, which means that the sinews of sanity must be suitably ministered to (and the right language for the ailment is vital for recovery.)