What is the difference between the meanings of selfish and self-assertive?

selfish:

1. looking after own desires: concerned with your own interests, needs, and wishes while ignoring those of others

2. showing that personal needs and wishes are thought to be more important than those of other people

http://encarta.msn.com/encnet/featur...fid=1861715914

1. devoted to or caring only for oneself; concerned primarily with one's own interests, benefits, welfare, etc., regardless of others.

2. characterized by or manifesting concern or care only for oneself:

http://www.infoplease.com/dictionary/selfish

self-assertive:

outspokenly assertive: tending to be aggressively confident in making your views heard and your presence felt

http://encarta.msn.com/encnet/featur...fid=1861715830

Determined advancement of one's own personality, wishes, or views.

http://www.thefreedictionary.com/self-assertive

confidently aggressive to advance one's own views

http://www.rhymezone.com/r/rhyme.cgi...self-assertive

insistence on or an expression of one's own importance, wishes, needs, opinions, or the like.

aggressively self-assured

http://dictionary.reference.com/sear...assertive&r=66

A selfish person is some what calm.
A self assertive person is aggressive in showing his selfishness.

Selfishness is defensive, and and self-assertiveness is offensive.