It is common knowledge that spending time outside in nature tends to improve one’s mental wellbeing. Attempting to explain this phenomenon, Attention Restoration Theory proposes that exposure to natural environments refills a certain depleted mental resource. However, research projects attempting to elucidate the psychological workings of this phenomenon have curiously inconsistent results. This paper proposes that this inconsistency can be attributed to the city aesthetic being used as the null condition/status quo against which the natural aesthetic is being tested as a restorative experimental condition. The fault in this arrangement is that the human mind’s adaptive relationship with the city aesthetic is not well established, especially in comparison to its stable affinity for natural environments, as posited by the biophilia hypothesis. Humans evolved in and with the help of natural environments, and their recent exodus from these environments into increasingly unnatural urban landscapes has resulted in psychological detriments that are simply alleviated when spending time in nature. This paper discusses the evolution of the urban aesthetic, its biophilic and biophobic elements, and the complicated nature of modern humanity’s relationship with the city, all of which render it highly inadvisable for use as a null condition in ART studies.