There are different theories and tools used to persuade people by changing their perceptions to agree on 
a idea/topic/act. Beuchet Chair is one such illusion theory which could provide could interesting insights on persuasion.
In the Beuchet Chair effect, the seat of the chair is at a distance from its feet, but from a certain vantage point, the parts appear as one whole chair. When someone sits on the seat now, we believe the person is as close to us as the feet of the chair. The person, however, seems a little too small – as she really is further away.
This was first introduced by Psychologist Jean Beuchet in 1963.
Resonvate Thought:
If one looks beyond the illusionary aspects involved in the Beuchet Chair effect , it does provide insights to designing marketing campaigns,improving brand perceptions,garnering support for social cause movements. Just Resonvate!
Reference
http://kinder.univie.ac.at/en/404.htmlhttp://apps.usd.edu/coglab/schieber/psyc301/BeuchetChair.html
