I suggest an engineering experiment to recognize — or, more likely, be reminded of — a biological reality with social significance. You won’t even need actually to perform this experiment, because you should be able to imagine it by physical facts you already know.

First, take the plug for your electric toaster in one hand and the plug for your electric coffee maker in the other. Then hold the prongs of the two plugs together.

Did you get either toast or coffee?

Again. Take an electrical receptacle (such as one made to be emplaced in a wall) in one hand and hold it against another electrical receptacle already in the wall.

Did the lights go on?

Have your lights gone on yet?

Some things are designed and made to be different but compatible in order to work together to produce something to which both contribute but neither can produce by itself.

When I was a school boy, we giggled nervously when our manual training teacher, in explaining electrical devices, used the technical and vividly descriptive terms “male end” and “female end” or “male plug” and “female receptacle.” But this is the fact of electrical mechanics, as well as what we had been “learning” in whispers at the back end of the playground and what our fathers had been trying to explain, artlessly.

Male and female are biological facts upon which life depends and had been since the dawn of time. So, it was honest and natural the concepts of giving-and-receiving, initiation and response, should lend a useful term to mechanics. Further, they have significance for emotional experience and social relations.

This may not be a perfect analogy, but, then, few analogies are. They are intended to draw a parallel; and when the parallel is recognized and the principle applied, we learn something useable.

Finally, this is not as much an analogy as it is an allegory or parable. Allegories and parables are told or written but not explained. They offer the opportunity for the hearer or reader to recognize the interpretation and make the application—and to accept responsibility for it.