Vol. 19 Num. 2 (1999) Daniel Chazan , Deborah Ball Beyond being told not to tell2 Peter Appelbaum The stench of perception and the cacophony of mediation11 Tim Rowland Pronouns in mathematics talk: power, vagueness and generalisation19 Maria G. Bartolini Bussi , Maria Alessandra Mariotti Semiotic mediation: from history to the mathematics classroom27 Leone Burton Communication: Exploring and reporting upon the content and diversity of mathematicians' views and practices36 Dimitris Gavalas Communication: A four-sided view of 'function'38 Ian Stevenson A journey through geometry: sketches and reflections on learning42