During this magic, the performer takes out a set of playing cards and mess them up before the audience. Then he pinches the lower two corners of the cards with his two thumbs and index fingers, lays the cards open face to the audience, pushes the cards to two parts and lets the audience see clearly the one in middle and puts them together. Then, he moves the cards behind his body, pushes the cards to two parts as before. He really picks out the same card identified by the audience. 

The magic only requires a set of half-worn playing cards. After messing up the cards, he pinches the lower two corners of the cards with his two thumbs and index fingers. When he pushes the cards to two parts, the card with the lowest friction coefficient will become the first one pushed open.  

After that, the same card will also be first pushed open if the cards are not rearranged because the smoother the card, the lower the friction. No trick but the principle of friction in physics is applied in this magic performance.