You can't debunk 9/11 cause the evidence speaks for it self. It is empirical, it too is also understandable if your fellow man does not view it as a farce, psychologically speaking the nature of the event affects the perceptive schema- the observers world view is challenged and in moments of terror, questions will be answered and memory gaps will be filled plausibly through abstraction by the observer.Human perception occurs by a complex, unconscious process called abstraction, in which certain details of the incoming sense data are noticed and remembered, and the rest forgotten. What is kept and what is thrown away depends on an internal model or representation of the world, called by psychologists a*schema, that is built up over our entire lives. The data is fitted into this schema. Later when events are remembered, memory gaps may even be filled by "plausible" data the mind makes up to fit the model; this is called*reconstructive memory. How much attention the various perceived data are given depends on an internal value system, which judges how important it is to the individual. Thus two people can view the same event and come away with entirely different perceptions of it, even disagreeing about simple facts.