Chronology of the modern reappearance of the ‘sagging horizontals’ myth

Ascertain when, in modern architectural discourse, the claim that straight horizontal elements appear to sag re-emerged and how it became acknowledged, including its transmission through Penrose’s work.

Background

The paper traces the ‘sagging horizontals’ explanation to Vitruvius but notes uncertainty about when this idea re-entered modern scholarship.

It highlights Penrose’s influential acceptance of a Vitruvian rationale as a pivotal moment, yet states that the precise timing of the myth’s reappearance remains unclear.