The Four Horsemen was a sound poetry group of Canadian poets composed of
bpNichol, Rafael Barreto-Rivera, Paul Dutton and Steve McCaffery. They
started performing in 1970 and quickly moved from radical improvisation
to the use of a notational system, with an effort to develop a scoring
method adequate to the group's dynamic and visceral sound show. The
four-piece soon became a living workshop with regular weekly rehearsals
leading to the best refined group-conceived and group-written
compositions