I remember, some time ago, reading a book that dealt with the multiple spheres of intelligence that supposedly exist that some people do better than others. The value of most of these domains of intelligence is well-recognized and celebrated. Verbal intelligence is cultivated in the ability to read, write, and speak in one’s own language or other languages, and this sort of intellect is highly valuable to those who possess it. Numerical intelligence is not necessarily as popular within the general population, but governments in particular as well as institutions of learning are quick to reward those with competence in such areas in the STEM fields with academic prizes, scholarships to institutes of higher learning, as well as remunerative jobs. Skill in artistic fields leads many to be poor starving artists but leads them in hope to receive cultural power for the art that they create, and sometimes the joy and skill at creation is compensation enough for all of one’s trouble. Mechanical skill is easy to celebrate, and of vital importance in the workings of our machinery and electronics, and no one will ever hear from my lips any contempt for those who are skilled tradesmen with such intelligence, even if I do not possess it in any great amount. Interpersonal intelligence is one whose attainment is of vital importance for those who deal with people, and is essential in areas of management and politics in any institution where being able to work well with others is of vital importance, which is to say, everywhere. Similar praise and worth is heaped in general on almost all forms of intelligence that can be posited, whether or not they are interconnected in any way with some sort of general intelligence or if they are entirely separate domains, or some combination where some are interrelated but others are not.

But one form of intelligence that the book presented is not at all obvious or easy to understand, and it is often neglected, and that is intrapersonal intelligence. First of all, it is difficult to define it. How can one possess an intellect in knowing oneself, after all? And if one could define what it meant, how is one to cultivate such an intellect? It is by no means clear that possessing a reflexive tendency towards reflection or a high degree of self-absorption is useful in acquiring genuine insight about oneself, nor is it always easy to turn self-knowledge into something that is actionable and beneficial to one’s life. Artists as diverse as Eugene O’Neill, playwright of A Long Day’s Journey Into Night, and contemporary musician Taylor Swift in her recent album Midnights have shown a remarkable ability to understand their own internal state and their own weaknesses and self-destructive tendencies. But knowledge does not mean overcoming or improvement, but rather a melancholy self-awareness. Nor, in an age where self-esteem has led to a dramatic decline in genuine self-awareness and an ability to recognize one’s true strengths and weaknesses, one’s shortcomings and the limitations that one has to struggle against that one is often shielded from by well-meaning people, is it easy to cultivate intrapersonal intelligence even if one could define it well.

What is the value of it, though? Let us give an example. Suppose that someone has an incurable but treatable chronic condition that can be exacerbated or moderated by one’s own behavior. Intrapersonal knowledge is very useful in such a case, as it allows one to know what to do and what to avoid to help stay in reasonably good health. Often this intrapersonal knowledge is hard won, thinking of one’s behavior as a controlled experiment where you test different variables to see the limits of one’s capabilities, the state of one’s vulnerability to various inputs, and so on. Not everyone is equipped to think of themselves as a test subject in experimentation, but that is likely how one’s doctor sees you if they give you lots of medication to try and find the right mix of medicines, looking at the doses as well as side effects. The goal of acquiring self-knowledge is to allow one’s life to be better, by managing one’s conditions and knowing what one can and cannot handle, what one needs to do and needs to avoid for one’s own sake. This is worth something. To know is not the thing, to do is the important matter.

Ultimately, even if we consider intelligence to be largely a cerebral matter, its value is in what it allows someone to do. I once knew a person who claimed to be an expert in how people in Southeast Asia thought with regards to their deep concern for face and avoiding being humiliated or embarrassed, but such knowledge did not prevent this person from regularly berating and abusing others, regardless of their background or their position, if they were below him, while he obsequiously flattered corrupt generals and royal courtiers who were above him in status. What value would it be to know a plumber or an electrician who had theoretical knowledge in how pipes or a circuit box worked but not ability to help you with your problems in either? Such examples could be multiplied ad infinitum. If knowledge makes us proud, being able to do something with it is what makes that knowledge useful and beneficial to others, whether we practice it to deal with the problems and burdens of this world or whether we teach others to improve their own capabilities to cope with life and its challenges. This includes knowledge about ourselves. The knowledge is itself a means to an end, and that end is living a better life.