The Vitruvian triad includes beauty, firmness, and what element related to use?

The Vitruvian triad, established by the ancient Roman architect Vitruvius, consists of three key principles that define good architecture: beauty, firmness, and utility. The element related to use in this context is ‘utility,’ which emphasizes the importance of a building's functionality. This principle highlights that architecture should not only be aesthetically pleasing (beauty) and structurally sound (firmness), but also serve a practical purpose.

'Usefulness' captures this essence of utility in architecture, as it implies that a structure must meet the needs and requirements of its occupants. This ensures that the building serves its intended function effectively, making it valuable and relevant in daily life. The focus on usefulness as a core element of the Vitruvian triad reflects an understanding that architecture must be practical and conducive to the activities that occur within it.