A couple of years ago, I was poking around in a European art museum and came across an exhibit of exquisitely beautiful Eastern Orthodox religious paintings, “icons.” Beyond being visually striking — they have an austere, hieratic, distant quality — they are also, I realized at the time, in a way, scientific.

Alright, I know, that’s a wild statement. But hear me out.

A religious icon is more than a painting. It has a semiotic value that’s highly codified, a language and practical purpose of its own that sets it apart from all the other representational art preceding our modern era of abstraction. This is partly because it’s such an ancient form of art, one dating back to a time when making images at all was a relatively rare gesture. It’s also because it’s a devotional form, a way of representing something believed to transcendent and beyond human understanding. This last point is what interests me.

An icon is somewhat fraught: it’s not entirely intended to be an object of its own. Rather, its purpose is to be a likeness, a tangible object that stands for an idea by signifying or representing it. In Christian theology, to worship an icon itself (remember the golden calf?) is blasphemous, and yet religious icon paintings date back to the 3rd century and are a major part of both Eastern Orthodox Christianity and Catholicism. This is because of a subtle semantic distinction: while worshiping an idol is frowned upon, worshiping via an idol is different.

St. Basil the Great, an influential 4th century Christian theologian and monastic, explained this concept by noting that “the honor shown the image passes over to the archetype,” that is to say the entity or object which it represents. He also illustrated further, “If I point to a statue of Caesar and ask you ‘Who is that?’, your answer would properly be, ‘It is Caesar.’ When you say such you do not mean that the stone itself is Caesar, but rather, the name and honor you ascribe to the statue passes over to the original, the archetype, Caesar himself.” In a sense, an icon of Caesar, or Jesus, is a two-dimensional window into the sublime, a conduit by which we can make tangible and understood something which is by definition transcendent and beyond the limited scope of human understanding.

Now let’s look to the definition of the word “diagram:” according to Wikipedia, a diagram “is a two-dimensional geometric symbolic representation of information according to some visualization technique.” Often, a scientific diagram — or a mathematical equation, for that matter — is not only a two-dimensional representation of something three-dimensional, but a representation of something that is without form. A relationship, a quality. That is to say, by definition something that’s transcendent, or beyond the limits of ordinary experience.

I think it’s safe to say that in the case of mathematics, or scientific diagrams, we also pass “the honor to the archetype.” We work with diagrams and symbols because they are the only way for us to bat around massive, immaterial concepts with any dexterity, and the final results of our work — which often appear as strings of numbers, symbols, and lines on paper — can have implications which are massive, far-reaching, and, while I hesitate to use the word “spiritual” for obvious reasons, certainly philosophical.

Edward Tufte, the statistician and recent presidential appointee put this point quite elegantly in a 2004 interview with the Technical Communication Quarterly :

The commonality between science and art is in trying to see profoundly–to develop strategies of seeing and showing. This seeing is not about “Aren’t these pictures of molecules beautiful?” Rather, the point is to recognize the tightness between seeing and thinking on an intellectual level not just a metaphorical level. That tightness is expressed in the very physiology of the eye: the retina is made from brain cells; the brain begins at the back of the eye. Seeing turns into thinking right there.

Both Orthodox icons and the symbolic language of scientific diagrams are placeholders, totems; their reality exists independently of their representation of it. Again, the same could be said about mathematics, a set of symbols which articulate a far more profound, invisible presence. As Tufte writes, these things serve to turn seeing into thinking. Aside from the obvious differences, the clear distinction between these religious icons and their secular, scientific equivalents is that they operate from different ideological bases: one is based on faith, and the other on knowledge. But the notion that these labors of mankind reach their apogee in what in the end are merely symbols, indicators, and arrows which point toward the actual, ineffable, unrepresentable reality of existence is an important thing which unifies spiritual “irrational” religious and “rational” scientific thought.