Read the passage below regarding the history of the Chicago skyscraper. Then, arrange the extracted claims in order of their logical hierarchy of support, starting from the most foundational factual premise (1) and ending with the overarching main conclusion (4).
Traditional architectural histories frequently trace the emergence of the late-nineteenth-century Chicago skyscraper to the fortuitous convergence of new structural technologies—specifically, the Bessemer steel frame and the safety elevator. While undeniably essential, this technological determinism obscures the primary catalyst for vertical expansion. The definitive driver of the Chicago School’s architectural innovation was, in fact, the hyper-commodified urban real estate market that emerged following the Great Fire of 1871. As speculative capitalism concentrated commercial activity within the narrow confines of the Loop, land values skyrocketed to unprecedented levels. To maximize the ratio of rentable floor space to the exorbitant cost of the underlying lot, architects were compelled to build upward. Consequently, the celebrated aesthetic and structural breakthroughs of the Chicago skyscraper must be understood not as the inevitable expression of new materials, but as pragmatic solutions to acute economic pressures.
- 1Following the Great Fire of 1871, land values in Chicago's central commercial district skyrocketed.
- 2To offset the exorbitant cost of small urban lots, architects were forced to maximize rentable floor space by building upward.
- 3The structural and aesthetic breakthroughs of the Chicago skyscraper were fundamentally pragmatic solutions to acute economic pressures.
- 4The hyper-commodified real estate market, rather than the mere availability of new technologies, was the primary catalyst for the architectural innovations of the Chicago School.