PV = kT

While you may not recognize it, the equation above describes a relationship between heat, pressure, and volume that you understand intuitively. It’s Boyle’s Law, one of physics’ easier bits. It’s easy in part, I suspect because it has intuitive parallels in your dealings with people, parallels that you might well encounter during this holiday season.

In 1662, Robert Boyle noticed that at a constant temperature, the pressure (P) and volume (V) of a fixed quantity of gas are inversely related. The more pressure the less volume, the less pressure the more volume. Raising temperature (T) increases pressure or volume but at different rates for different gasses, so there’s a constant (k) for each one.

Mind Readers Dictionary: The Podfast : Play in Popup

Mind Readers Dictionary : Play in Popup


In psychological parallel, what it boils down to is this: Social interaction in close quarters is likely to cause some heated interactions.

Pressure (P) is a measure of the force generated by gas molecules as they bounce against each other and the walls of whatever contains them. And so too with people. Pressure is the force of impact in an encounter. People put pressure on each other to change. A lot of pressure makes people “bounce off the walls.”

Volume (V) is the size of the container that holds the molecules or people. If you increase the volume, the frequency of encounters goes down. Couples living in separate or larger houses have more volume (space) than couples who share studio apartments. Over the Christmas holidays the volume containing family members shrinks as people converge from all over the country for a warm encounter. Too warm and people need to “create some space” or else they might explode.

Temperature (T) is a product of the energy between molecules, which can be increased from the outside by heating. So too with people. Outside forces can energize us, making us more forceful in encounters within our containers. An outsider might urge or inspire one family member to put more pressure on another. Your partner tells you that you should stand up for yourself against your father, that you should convince your brother to stop drinking so much. Family members come home for Christmas all excited about a new way of doing things that they learned about from an outsider, eager to put pressure on the rest of the family try it.

I must clarify at this point: I’m not claiming some deep true similarity between gas molecules and people; I’m just noting an interesting or curious parallel that feels true enough to have found its way into folk psychology through various phrases. It’s what’s known as a “heuristic metaphor,” good for insights regardless of whether it is a real parallel.

Getting back to physics: Different molecule types respond to temperature increases differently. Some are more volatile than others. The constant (k) differs for different types of molecules, meaning that a temperature increase causes different increases in pressure or volume depending on the molecule type. So too with people. Some of us are more volatile than others, quicker to distance ourselves (increase volume) or confront (increase pressure) than others. The psychological analog to (k) is something known as “neuroticism,” the fifth personality trait in the five-factor model of personality that is generally considered more accurate than the four-factor Meyers-Briggs. Neuroticism is associated with anxiety, angry hostility, depression, self-consciousness, impulsiveness, and vulnerability. The higher the neuroticism the larger the k value—the greater volatility.

Gas molecules don’t change constants, but can we? Can we become less volatile? If so, by what mechanism? Of interest to me lately is our ability to create psychic distance. That is, to expand virtual volume—to give someone space without leaving, to distance ourselves from them in our minds while remaining physically present to them. It’s a great source of sustainable serenity, though it’s also a source of uncertainty and danger in relationships. Here’s an illustration. See if the dynamic doesn’t feel familiar even though the dialogue is contrived:

Disrespected person: I want you to respect me.

Disrespecting person: Uh, OK, I respect you. (Having moved one psychic step away.)

Disrespected person: Honestly?

Disrespecting person: Well, no, not honestly.

Disrespected person: No, I want you to honestly respect me.

Disrespecting person: OK, I honestly respect you. (Having now moved two psychic steps away.)

Disrespected person: Really?

Disrespecting person: Sure. (Having now moved three psychic steps away.)

Psychic distance, expanding the volume encompassing you and another person, is a social lubricant, a source of civility, politeness, and equanimity, a way to reduce pressure by increasing virtual volume (creating space). It’s also the source of latent distance and pressure, the stuff that makes people unnervingly hard to read. Accumulated psychic distance can turn into real distance very quickly. “I’m leaving. I haven’t really loved or respected you for a long time.” Or it can flare into a sudden burst of pressure. “For years I’ve hated the way you behave. You had better change now, or else.”

We therefore read each other very closely for the accumulation of psychic distance. There’s a whole language of inflections around the word “really.” “No, reeeeally.”

And we can play with the edge between virtual and real distance as a way of conveying pressure. The twitch of a critical eye, a barely audible laugh of exasperation, an “I’ll give you space” that’s really a just-above-below-the-radar way of leaving in a huff or abandoning the other person. We all have a million ways to apply pressure with impunity. Indeed every way of not pressuring can, with the slightest nuance, become a way of pressuring. Silence is either golden or cold, depending.

So is it good, this social lubricant? Shouldn’t you just respect everyone? Of course, in the abstract, meaning with enough real space between you and a person who rubs you the wrong way, you can maintain some kind of abstract tolerant regard. At close range, or contained within a formal volume (the family, a marriage, a business partnership) the pressure increases, and something has got to give. Should you just give in to the pressure? Sometimes, not always. Should you engage in conflict? Sometimes, not always. Should you live and let live by feigning intimacy while keeping the other person at a psychic arm’s length? I suspect this may be the most efficient move even though for some of us more volatile types it’s hard to do.

I love my partner in part because she’s got an extremely low k value. She can absorb all sorts of heat with equanimity. I’m by temperament more volatile. Being with her I find I can expand my repertoire to include a bit more expansive capacity, the ability to create psychic space. I find I’m already a bit less compelled to either challenge people whose ideas I don’t respect or run howling a good long distance away from them.

I love my partner also because we share in common an appreciation of the benefits and costs of high and low volatility. We both understand that it is possible to condescend through kindness, and conversely to show respect through confrontation.

May your holiday season be filled with good judgment calls about when to pressure, when to make space, and when to create psychic space to keep things cozy.