用眼睛长时间凝视图中间竖排的四个小黑点大约１５－３０秒，然后闭上眼睛，一直闭着，你会看见一个光圈，在这个光圈里……你见到了谁？
Look at the 4 points in the centre of the picture for 15~30 seconds, then close your eye. 
Who do you see when you closed your eyes ?

 
看着哪个，哪个就不动～
its moving? but its motionless actually.