Quotation for Pesachim 51:20

The remaining factor to be considered is whether mere visual examination undertaken solely for aesthetic or recreational purposes constitutes a forbidden form of benefit. "Benefit," in the fundamental halakhic meaning of the term, connotes tangible physical benefit such as eating, drinking, anointing the skin or financial enrichment. Thus, the Gemara, Pesaḥim 26a, declares, "Sound, sight and smell do not constitute me'ilah (kol, mareh vareaḥ ein ba-hen mishum me'ilah)." "Me'ilah" refers to prohibited use of consecrated property for mundane benefit. In context, the Gemara is defining and limiting the concept of hana'ah, or benefit. Although other forms of sensual pleasure do constitute hana'ah, benefit derived by means of "sight" does not rise to the level of a prohibited "benefit." The principle is made explicit with regard to the prohibitions concerning me'ilah but, logically, it is equally applicable to all categories of issurei hana'ah.