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In brief the stylistic dilemma was a product first of the Renaissance (which gave us the idea of individual style), and then of Romanticism (which gave us the idea of a multiplicity of styles). [...]
It was in the area of romantic landscape that the idea of appropriate form, that is a style appropriate to a particular context, first came to fruition. Of course the idea had a long history. Vitruvius endowed the different classical orders with distinct characters - masculine Doric, matronly Ionic, and so on - establishing a classical tradition of decorum, or manner, and this variation and stylistic differentiation; ideas which in turn were developed in eighteenth-century France. J.-F. Blondel explained the appropriate use of style as a kind of 'colouration', 'the poetry of architecture'. 'In a word', he suggests, 'style... enables the architec to create a sacred genre, a heroic one, a pastoral one'. Ledoux took such ideas of stylistic expression a good deal further, designing buildings such as his notorious phallic-shaped brothel, or his barrel-shaped house for a cooper or barrel-maker, which are themselves three-dimensional metaphors. Architecture thus becomes a symbolic language.
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In the early eighteen century - the cultural watershed when nature replaced religion as the motive force for creative artists - the cult of styles had become rooted in the soil of the Romantic landscape. But it was not until the early nineteenth century that choice developed into conflict. [...] Buildings were now pictorially conceived as memories in three dimensions [...].
The habit of regarding buildings as scenery - as aggregates of separate visual units - encouraged not only irregular skylines and asymmetrical plans, but triangular, hexagonal, and octagonal features, eyecarcher and all manner of follies [...]. Picturesque thinking was certainly an encouragement to drawing-board architecture: designing a house from the outside inwards, rather than from the outside outwards - a process of design ideal for landscape features. Carter's triangular fort is reciprocally picturesque: a building designed to be looked at as well as looked from; an example of scenographic design, based on the multiplications of points of vision."
Van Eck, Caroline; McAllister, James; Van de Vall, Renée (eds.) (1995) The question of style in philosophy and the arts. Cambridge University Press, Cambridge.