The Collaborative International Dictionary of English v.0.48:

Self-evident \Self`-ev"i*dent\, a.
   Evident without proof or reasoning; producing certainty or
   conviction upon a bare presentation to the mind; as, a
   self-evident proposition or truth. -- Self`-ev"i*dent*ly,
   adv.
   [1913 Webster]

WordNet (r) 3.0 (2006):

self-evidently
    adv 1: in a self-evident manner