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Chapter 4 · Exploring Some Geometric Themes

Fractals in art: temple, textile and print built by repeating the whole at a smaller scale

यह वीडियो हिंदी में भी · Watch in Hindi

Fractals9 min

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9 min.

Also recorded in Hindi.Englishहिन्दी

People were building these long before anyone had a word for them. Perhaps the oldest still standing are temple towers.

The idea

The temple, the blanket and the print are not surfaces with a motif applied to them — they are built by the rule that also produced their own outline, which is why the eye reads them as "the whole thing again, smaller". That makes self-similarity a construction method rather than an ornament, and it has a consequence you can test: if the rule really is self-application, then knowing one level lets you predict the next. The mathematical fractals of §4.1 run the rule forever; the artworks run it three or four times and stop, because stone, thread and ink each have a smallest mark. The idea is the same; only the number of steps differs.

What you should be able to do

  • Apply the magnify-a-part test to a photograph or a textile and decide whether the structure is self-similar
  • Identify, in the Khajuraho temple, what plays the role of the whole and what plays the role of the copy
  • Count the levels of nesting visible in a given artwork and say what limits that count
  • Explain why a physical object can only ever be an approximation of a fractal
  • Distinguish a tiling from a fractal, given that both repeat a unit
  • Describe the Fulani blanket's structure as nested diamonds and say which property makes it self-similar rather than merely patterned
  • State, with the chapter's own hedge, the claim about the age of fractal structure in Indian temple architecture
  • Design a small self-similar ornament by choosing a shape and a placement rule, and run it two levels

Words to know

TermDefinition in one lineFirst introduced
fractala shape whose parts, magnified, reproduce the wholeprinted in this chapter (Part II, §4.1, p.70)
self-similarhaving parts that are scaled copies of the wholeprinted in this chapter (Part II, §4.1, p.70)
tilingcovering a surface with repeated shapes that leave no gaps and do not overlapprinted in this chapter (Part II, §4.1, p.75)
scalethe size at which a copy is made relative to the originalprinted in this chapter (Part II, §4.1, p.70)
templethe built structure the chapter uses as its oldest exampleprinted in this chapter (Part II, §4.1, p.74)
printa work of graphic art, the form Escher worked inprinted in this chapter (Part II, §4.1, p.75)
level of nestinghow many times the copy-inside-a-copy relation is visiblean added term; the chapter describes nesting in words and gives it no name
approximationa finite construction that stands in for an unending onean added term, not printed in this chapter
motifa decorative unit that is repeated without containing copies of the wholean added term, used here only to name what a fractal is not; not printed in this chapter

Where people slip up

  • "The temple has a pattern carved on it." The self-similarity is in the massing — the shape of the building itself — not in surface decoration. A pattern carved on a plain box would not be self-similar at all.
  • "Any repeated ornament is a fractal." Repetition side by side is a tiling. Repetition inside is self-similarity. The blanket is interesting precisely because it does the second, and the chapter's own sentence about diamonds inside diamonds is what marks the difference.
  • "Escher's tilings are fractals." The chapter separates them: tiling is one theme of his work, fractals another. Smaller and Smaller is the fractal one because the same figure recurs at reduced scale, not merely repeated.
  • "The print on the page is by Escher." It is stated to be inspired by his work. Getting this wrong is a factual error and an attribution error at once.
  • "Real objects are fractals." No physical object can be, because every material has a smallest workable mark. They are finitely many levels of a fractal construction, which is a different and weaker claim — and the honest one.
  • "Indian temples are the oldest fractal art." The chapter says perhaps, and an explanation that drops the hedge has strengthened a claim the textbook declined to make.
  • "You need the drawing to know what comes next." You need the rule. Given the rule, the next level is determined; given only a drawing of two levels, it is not. This is the section-11 payoff and the reason the topic is mathematics rather than appreciation.
Transcript1,304 words

People were building these long before anyone had a word for them. Perhaps the oldest ones still standing are temple towers, and the word perhaps is doing real work in that sentence. Nobody has checked every building tradition there has ever been. What makes a tower one of these is not the carving on it. It is the shape of the building itself. The tower is made of smaller towers with the same profile, and each of those carries smaller ones again.

A wedding blanket, woven a continent away, does the same thing with diamonds. Diamonds holding diamonds holding diamonds. And a printmaker, much later, made a print in which the same interlocking figures come back smaller and smaller towards the middle. Three materials, three traditions, one idea, and this is about what that idea actually says. Start with the word that causes all the trouble. Repeat. There are two completely different things it can mean, and telling them apart is the whole of this.

You can repeat something beside itself. A row of identical diamonds along a border, each one full size, none of them holding anything. Or you can repeat something inside itself. One diamond, holding smaller diamonds, each of those holding smaller ones again. Both of those are repetition. Only the second one is what we are after. Laid beside, or set inside. Everything from here follows from that. So here is a test you can actually run, instead of an impression you either have or do not.

Ring one part of the thing. Blow that part up until it is the size of the whole. Now look at it, and ask what you are looking at. If it is the whole thing again, it passes. If it is something else, it fails. Ring, magnify, compare. That is the entire test. Run it on the border of diamonds. Ring one diamond, blow it up, and you are looking at a diamond.

But the border was a row, and a diamond is not a row. It fails. Now run it on the nested diamond. Ring one of the small ones, blow it up, and you have a diamond holding smaller diamonds. That is the whole thing again. It passes. The same shape on the page, and opposite answers. Of eight structures put through this test, three of them pass. The point of the other five is that every one of them is something people happily call a fractal, and none of them is.

Take the tower first. Ring one of the smaller spires standing against its side. Blow it up, and its outline is the outline of the whole tower. The same silhouette, the same stepping. So it passes, and what passes is the massing. The shape of the stone itself. That matters, because it rules out the reading almost everyone reaches for first. A plain box with a beautiful pattern carved on it is not this.

There, the pattern is on the surface. Here, the building is the pattern. The blanket is the same test run on thread. Ring one diamond in the woven field. Blow it up, and it turns out not to be a plain diamond at all. It is a diamond holding smaller diamonds. Ring one of those, and you get the same answer again. Which is why the interesting thing about that blanket is not that it has diamonds on it.

It is that the diamonds are made of diamonds. Now the trap, because there is an obvious wrong test and it is the one people reach for. The wrong test is: does it have smaller copies inside it? Take a plain box with small flowers carved into its face. Smaller shapes, set inside a bigger one. It passes that test without any trouble. But ring one flower, blow it up, and you are looking at a flower. Not a box.

Of the eight, five have smaller things inside them, and only three are self-similar. The two tests agree on six of the eight and part company on two, and both of those are carved boxes. Smaller things inside is what decoration looks like. It is not what this is. There is a second wrong test, and it is even easier to reach for. Does it repeat? Six of the eight repeat something. Three are self-similar.

They part company on three of them: the border, a tiling, and the carved box again. A tiling covers a surface with one shape over and over, no gaps and no overlaps, every tile the same size. Magnify a tile and you have a tile. The printmaker's shrinking figures are a different thing entirely, and the difference is that one word. The figures come back smaller, inside. Not beside. Underneath all three is a single instruction, and it is worth saying slowly.

Pick a shape. Pick where the copies go, and how much smaller they are. Then apply that same instruction to every copy you just made. That last clause is the whole thing. Not: put some big copies down, and then some small ones. But: whatever you did to the whole, do to each copy, and then to each copy of each copy. Which is how one instruction produces a shape that nobody drew.

The maker chooses a rule. The drawing is what falls out of it. And here is why that is not word-play. Take a triangle. On the middle of each side put a copy at half size. Then do it again to every copy. After two rounds you have one, plus three, plus nine. Thirteen pieces, in three different sizes. Now imagine somebody else made exactly that picture a different way.

They placed three half-size copies, then nine quarter-size ones, and stopped, because that was all they were ever going to do. Piece for piece and size for size, the two pictures are identical. But run each of them one more round. One has forty pieces in four sizes. The other still has thirteen in three. The difference is twenty seven pieces, all of them at one eighth, and there is nothing in the two-level picture that says whether they are coming.

A drawing of two levels does not settle the third. The rule does. Which raises the obvious question. Why does the real thing always stop? Because every material has a smallest mark it can make. A chisel has a smallest cut, a loom a smallest thread, a press a smallest dot. Say the smallest mark is a tenth of the whole. Copies at half size give you three levels. Copies at a third give you two.

Make the material a hundred times finer and you do not get anything like a hundred times the levels. A mark a hundredth of the whole gives six and four. A thousandth gives nine and six. Levels come slowly, however good the material gets. The mathematics has no smallest mark at all, and that single difference is the whole gap between the model and the thing. So build one. Pick a shape, a triangle. Pick a rule: three copies at half size, one on the middle of each side.

Round one gives three. Round two gives nine. One and three and nine is thirteen. Now change one number. Four copies at a third instead, and the counts run one, five, twenty one, eighty five. Same idea. Different object. And that is the thing worth taking away. What the maker chose was never the drawing. Run this rule ten levels and it has placed over eighty eight thousand pieces, quite happily, long after any chisel would have given up.

A mason, a weaver and a printmaker each ran the same instruction as far as their material allowed, and then stopped. Not because the idea ran out. Because the stone did.

Where this fits

Taken from the notes each video was made from, not from the reading order — these are the ideas this one rests on and the ones that later rest on it.

Builds on

Either side of this one

The book

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