“…Formally, structures that can be understood as recursive have been suggested to exist in visual art ( Eglash, 1997 ), visuo-spatial processing ( Martins, 2012 , Martins and Fitch, 2012 ), music ( Jackendoff and Lerdahl, 2006 , Lerdahl and Jackendoff, 1996 ), architecture ( Eglash, 1998 ), humour ( Eisenberg, 2008 ), theory of mind ( Miller, 2009 , Tomasello, 2008 ), problem solving ( Schiemenz, 2002 ), action sequencing ( Pulvermüller & Fadiga, 2010 ), syntax ( Chomsky, 1995 , Karlsson, 2010 , Mithun, 2010 , Roeper, 2009 ), phonology ( Hulst, 2010 , Hunyady, 2010 , Schreuder et al, 2009 , Wagner, 2010 ), pragmatics ( Levinson, 2013 ), conceptual structure ( Hofstadter, 2000 , Picard et al, 2010 ), mathematical proofs ( Odifreddi, 1999 ), natural numbers ( Hauser et al, 2002 ), and arithmetic operations ( Friederici, Bahlmann, Friedrich, & Makuuchi, 2011 ). In all these domains it is possible to build recursive algorithms that generate hierarchical structures.…”