This trick has puzzled some of my friends !

[borogovio]

It's curious, and it has tricked many people ! My son actually was convinced that the computer could read his mind.

 

[paulie]

I like it, but how is it done?

Or am I just thick?

 

[bertieg]

All the cards disappear and 4 different ones come up.

 

[paulie]

Thanks bertieg, I see what you mean, also I should pay more attention to things ;-)