Back in the entrails of Piranesi's subterranean, in Plate VI we are surrounded by serpentine interior spaces that unfolds endlessly before our sight. Piranesi will call a truce only in Plate IX, only to never show us the outdoors again. In the spatial confinement of Plate VI, at the center of the illustration, a voluptuous cloud of smoke suggests that a battle is taking place. Human silhouettes and blurred artifacts are interwoven on the crowded passageway, from where we can also see wooden beams or what appears to be fragments of masts. Curiously, on the lower level, people are completely indifferent to the tumult, calmly strolling around as opposed to the pointing figures that seem desperate to find an exit.
Piranesi outlines several objects that resemble torture machines or conjure up the idea of painful sensations at the bottom of the plate. Colossal bollards can be read as a torture device called vergine di ferro (iron maiden); pulleys and ropes suggest the torment of corda (racking rope); and wooden fragments are complemented with spikes of different sizes and shapes.
Piranesi emphatically emphasized the psychological torture in his Carceri d’Invenzione. The hostility of the space and the lack of exits suggest an inevitable and tenebrous death. The human figures are lost and desperate in the confined architecture he created. People become trapped between the immense walls and infinite arches, as well as in the bridges that lead to nowhere, whereas others are apathetic to any threat that the scenario might invoke. To Piranesi, stagnation is torture. Likewise, the bad taste, or cattivo gusto, that the artist identified in the work of some of his contemporaries inflicted great pain.