Back in the very early 70's at York U there was a black activist if memory serves called Horace Campbell....and on the walkways between colleges there were a bunch of blacks sitting with their legs extended intentionally making a point for no whites to dare cross the aisleway.....kind of blocking anyone from walking across.....yet, with one swift forcefull mis-step onto each of  their nether-regions it immediately cleared the aisleway. History lesson!