Semper employed scientific research methods to understand classical architecture. Through his research, he hoped to rationally explain built form through a taxonomy of architectural style and form. According to Semper, all built form was divided into four categories; the hearth, the substructure or platform, the roof, and the enclosure Semper envisioned these ideas to be read not as chronological data, but as concepts that could undergo transformations either together or separately. Semper created a formula for style that placed a greater emphasis on function as having an effect on design rather than materials.
Ruskin conceived the seven lamps of architecture; sacrifice, truth, power, beauty, life, memory, and obedience as categories considered vital to architecture. The seven lamps of architecture promoted the virtues of the Gothic style. Gothic architecture resonated with Ruskin because it emphasized the importance of nature and natural forms. Ruskin disagreed with the theory of restoration; he believed restoration was in fact the most total destruction which a building could suffer. Restoring a building meant no remnants could be gathered and only a false description of the building that was destroyed would remain. Ruskin compared restoring a building to raising the dead, an impossible task.
Viollet-le-Duc wished to rationalize Gothic architecture and to understand how it came about. He wanted to focus on the evolution and development of architecture intent as it related to a building's structure. Viollet-le-Duc analyzed masterpieces of the past, reduced them to a process or argument and the he attempted to apply that logic in his work. He wanted to take the ideas of Gothic architecture and apply them to contemporary times with modern materials.
