The group of ancient ruins seen in this view was considered by Piranesi's contemporaries to belong to the Temple of the Sun and Moon. This engraving features in an argument that appears across Piranesi's works. From the outset, Piranesi declares his disagreement with his peers by titling the work "View of Two Dining Rooms Belonging to Nero's Golden House, taken erroneously [erroneamente] for the Temples of the Sun and Moon, or of Isis and Serapis." While it is true that Piranesi was never one to shy away from controversial claims, his most brazen statements were often reserved for the footnotes, annotations, or other explanatory and paratextual elements of his publications. By presenting his central argument in the title, Piranesi strategically highlights his novel identification of the site as part of the larger complex of the Domus Area of Nero, an argument he makes in three separate engravings in the Views of Rome. Perhaps the necessity for boldness came out of Piranesi’s contending with a long and established history of attribution. For example, he contended, in the key and in the image, with sources as authoritative as Palladio's Quattro libri dell'architettura (1570), considered the fundamental architectural treatise of the Renaissance. Only Giuseppe Vasi, Piranesi's mentor, in his Prospetto di Roma (1765), mentions a possible link to the Domus Aurea (Vasi, Indice, 54-55). However, the majority of eighteenth-century artists and antiquarians across Europe, such as Hubert Robert, Giovanni Canaletto, and Jean Barbault, largely upheld Palladio's description and reconstruction of the imperial monument (seen below).
Piranesi agreed with both Palladio and contemporary authors on certain key points: the main structure was composed of two large hemicircular chambers used in either summer or winter (as described in annotations 1 and 2 in Piranesi's engraving), the vaults of these chambers were decorated with stucco in a diamond and square pattern (seen in the central arch and in the upper story below annotation 2), and sculptures of "illustrious men" occupied niches throughout the building. In addition to the textual references to Palladio's treatise in the key, Piranesi visually alludes to the second plate of the monument, which shows the ornamental reliefs of the upper vault in detail. Tempering a bold claim with an established visual source, while ultimately correcting or disproving that source, was typical of Piranesi's approach to argumentation.
Piranesi cites archeological and geographical evidence to support his claims, which he first elaborates in the Antichità Romane. Piranesi asserts that observations made by "modern writers" have not sufficiently "considered the form of the ruins, which would have been enough to dissuade them from their suppositions” [I moderni Scrittori suppongono...senz' averne considerata la forma, la quale sarebbe bastata a ricredergli dalle loro supposizioni] (AR, Volume I Map, no. 282). The assumption of his contemporaries that any sort of apse or hemicycle would automatically indicate a temple, demonstrates just how "little knowledge” [poca scienza] they have of Roman architecture (AR, Volume I Map, no. 284). Anyone with the most basic understanding of domestic architecture, he goes on to argue, would know that virtually all Roman buildings have such features. The hallmarks of ancient Temples, such as a portico or pronaos (evident in the Pantheon for example), Piranesi demonstrates, are notably absent.
In addition to the formal features of the ruins, Piranesi argues that their geographical location, adjacent to the main hall of the Domus Aurea and the Colosseum, supports his revision of previous authors. Piranesi further elaborates this argument in his reconstruction of the Roman Forum (see the entire map here, detail below).
The print seen above corresponds to number 62, while the main complex of the Golden House of Nero is indicated at 57 and 58. The light hatching indicates Piranesi's conjectural plan of the buildings, while the darker shading indicates the extant ruins. The topographical reconstruction of the Golden House, in tandem with the visual evidence provided in the three engravings of the structure in the Views of Rome, prove Piranesi's argument that this particular ruin was a natural extension of the domestic complex built by Nero (Wilton-Ely, 52). It should be noted that contemporaries did not agree with Piranesi's assessment, and the building was considered to be the Temple of the Sun until only recently. The building has now been identified as the Temple of Venus and Roma. However, Piranesi's revisions show his willingness to go against the grain and, moreover, the ways that the textual and visual elements of the Views of Rome, which were aimed at tourists, featured in his broader archaeological arguments, written for a different audience, across the entirety of his œuvre.