Body and mind are deeply connected. Thinking of them as distinct is more a product of the intellect than a correct description of their reality. Often the body’s symptoms reveal the mind’s state and vice versa, but the body is more visible; it’s easier to observe the outside and work inward. Psychotherapists must collect more evidence before they can diagnose with ease in either direction.

There’s no lack of data. People present plenty of symptoms. However, everyone, especially therapists, seem to believe they already know how the mind works. This makes it hard to collect and consider evidence in a neutral, unbiased way. Most theories of the mind are, in effect, merely symptoms of the theorists themselves.

Another problem is that the phenomena of the mind are hard to measure accurately. So far, the clearest evidence lies with complexes, which are sets of behaviors that act outside conscious control. Complexes recur spontaneously, causing strife and agony; they are signs of urges a person doesn’t want to think about. Though painful, they serve as important clues that something is lacking or incomplete in a person’s life—something the person must resolve but can’t.

Typically, these problems begin in childhood. Nearly everyone develops a “parental complex” during early struggles to adapt to their parents, but these complexes evolve in widely varied ways and become signatures of everyone.