My apologies, I focused on only one misleading visual trick while the instigators of the twirling girl included several.

Yes, I approached the truth and but then turned away smug.

Now I see that the illusion works because the human mind tries to transform the visual odd into the visual familiar to facilitate infomation processing.

I only focused on the Coriolis effect of the circling i.e. when the shadow of the girl's foot turned clockwise I corrected for the girl's apparent motion and saw her turning counter-clockwise. But it turns out that the devious plan of this study was to disrupt conceptualizations by changing "several" key visual clues as she spun.

I promise I will never be wrong again.

Last edited by themilum; 10/15/07 10:50 PM.