"Two identical heads, sculpted in the likeness of an imaginary androgynous figure, speak to each other, doubting the reality of their own existence. These two, in ever-changing and outrageous conversations with each other struggle to determine if they really exist or not, if they are the same person or not, and if they will ever know. Ken Feingold wanted them to look like replacement parts being shipped from the factory that had suddenly gotten up and begun a kind of existential dialogue right there on the assembly line. Their conversations are generated in real time, utilizing speech recognition, natural language processing, conversation/personality algorithms, and text-to-speech software. They draw visitors into their endless, twisting debate over whether this self-awareness and the seemingly illusory nature of their own existence can ever be really understood." [1]

[1] http://www.kenfeingold.com/catalog_html/ifthen.html