Ancient Parthenon Myth About Optical Illusions Debunked
A mathematician argues that the temple's famous curves were not designed to correct visual illusions, challenging a 2,000-year-old belief.
A new study by an Oxford mathematician has challenged a long-standing architectural belief, asserting that the Parthenon's famed curves were not intentional corrections for optical illusions. For over two millennia, it has been widely accepted that the ancient Greeks incorporated these subtle architectural adjustments to make the temple appear straight and regular to the human eye.
The findings, published in the journal Royal Society Open Science, suggest that these architectural features are more likely products of their time rather than sophisticated optical engineering. Professor Alain Goriely, the mathematician behind the study, combined geometry, engineering, and vision science to investigate the claim. He concluded that there is insufficient evidence to support the existence of the alleged visual illusions.
"The Parthenon has been cast as an ultimate trompe-l'oeil, supposedly designed to exploit visual illusions in its curves and refinements," Professor Goriely stated. "Current historical and scientific evidence does not support these claims. The main lesson from the Parthenon is that we are prone to delude ourselves in the pursuit of ancient mysteries and ideal fantasies of order and harmony."
The myth's origins are traced back to the writings of the 1st-century Roman architect and engineer Vitruvius, who documented the Parthenon approximately 400 years after its construction. Vitruvius suggested that slight curvatures in the stylobates, the flat bases supporting the columns, were made to counteract the illusion of straight lines appearing to sag in the center. Measurements confirm that the Parthenon's base rises about 2.3 inches (6cm) in the center, a feature attributed by Vitruvius to correcting this supposed optical illusion.
However, Professor Goriely's calculations indicate that the sagging illusion itself may not be a significant factor for observers. Another common claim relates to the slight outward bulge of the Parthenon's columns, believed to correct the illusion that columns appear narrower in the middle. The study notes that these bulges are minimal, only about 18mm, and again, there is no evidence that such an illusion is perceptually significant.
Professor Goriely proposed an alternative explanation for the curvature in the stylobates: that small gradients could have facilitated water drainage, preventing puddles around the base of the columns. The study analyzed a total of 12 proposed optical corrections, finding them either unsubstantiated by evidence or too subtle to be noticed under normal viewing conditions.
The paper, titled "The illusion of illusions: there are no optical corrections in the Parthenon," states that the myth's persistence, despite a lack of direct evidence, highlights a human tendency towards constructing elaborate explanations for ancient artifacts. The belief in these optical corrections originated with Vitruvius and resurfaced in the 19th century with detailed measurements.
Separately, a previous study suggested that the Parthenon's attic may have once served as a treasury, potentially holding up to 260 tons of silver and gold. Researchers reconstructed the attic's dimensions, estimating it to be over three times the size of a tennis court. While the attic is now destroyed and the coins likely spent, the study indicated the space was large enough to store significant wealth and distribute its weight.