' … this book provides anyone concerned with welfare with abundant information and ideas on the advanced nature of primates' intelligence.' Animal Welfare 1998
'Whiten and Byrne are to be congratulated for collecting this second set of essays which are an important addition to the field of 'cognitive ethology'.' Aubrey Manning, The Times Literary Supplement
'Best of all, Mach II is in affordable paperback form the outset, and compels just as much attention as did Mach I.' W. C. McGrew, Journal of the Royal Anthropological Institute
'If you think you might want to read this book, yes, you do! That is, if you are interested in primate cognition, in 'mindreading' … or in the evolution of human social understanding, then Mach II is a book to seize on.' Animal Cognition