The essence of a building lies on its decorum, as well as how it promotes to national, social and cultural well-being. The very first idea of architectural decorum was coined by Vitruvius, in his book ‘De architectura’, wherein he explains the correct usage of ornaments, that is the precise usage of mosaic, paints and other materials required to establish roofs and porticoes etcetera in order to provide poetic and rhetorical meaning to the architecture .
Decorum defines how suitable the design of a building is and has been related to the way a building is shaped with regards to civic order and social standing . Since Vitruvius has already described decorum to include ornaments, it is interesting to note how Kohane has observed ornamenting architecture as James Fergusson’s distinction of art from the all-encompassing aspects of architecture (as proclaimed earlier by Vitruvius). Furthermore, the association of ornaments with architecture as a means of modernism in the nineteenth century also need to be explored in order to justify the architectural changes made by Governor Macquarie. Where the ‘appropriateness’ or suitability of a building is concerned however, the word decorum absolves architecture of ornaments and focuses instead on the logic and viability of the entire composition of the building .