The theories of tele-kenetics suggest that our brains are simply antennae.  They transmit and receive stuff just like your FM Radio or your Cell-Phone.  If these theorem are true, the answer to your second question (Are we all psychic) may be YES!  The ability to control these 'powers' is, however, the harder part.  Mankind as a whole will possibly never get the chance to master this skill.
How can I read minds? Are we all psychic?