Some people say you have 10 fingers.  Some people say you have 10 digits: 8 fingers and 2 thumbs.  Not to worry, though.  Zulumoon.com blog has got the situation under control.  We’ve pulled up our sleeves and consulted the ultimate source: NEWTON, the ask-a-scientist web collaboration of U.S. scientists, on an official government website.  The scientists say: “The thumb is actually a special finger that has only two bones [versus three bones].  ... The way that the muscles and bones of our thumbs are set up…allow for a motion called opposition."

The official conclusion?  You’ve got two special fingers!  And Zulumoon.com has a selection of affordable sterling silver thumb rings to adorn them.

information source: http://www.newton.dep.anl.gov/askasci/gen01/gen01987.htm