Vol. 30 Num. 1 (2010) Erik Tillema Functions of symbolizing activity: a discussion ABSTRACT 1 Jan Zwicky Mathematical analogy and metaphorical insight ABSTRACT 9 Vicenç Font , Juan D. Godino , Núria Planas , Jorge I. Acevedo The object metaphor and synecdoche in mathematics classroom discourse ABSTRACT 15 David Pimm Communication: 'The likeness of unlike things': insight, enlightenment and the metaphoric way20 Christopher Danielson Communication: What is ten? Relationship between language and numeration ABSTRACT 23 Stephen J. Hegedus , Luis Moreno-Armella Accommodating the instrumental genesis framework within dynamic technology environments ABSTRACT 26 Keith Weber Proofs that develop insight ABSTRACT 32 Sean Larsen Struggling to untangle the associative and commutative properties ABSTRACT 38 Margaret Rathouz Ambiguity in units and the referents: two cases in rational number operations ABSTRACT 44 - Contributor affiliations and contact information52