we could even wax philosophical and iterate:
every human being rips off pieces of his identity from her experience of the world around them as they grow and learn and experience, thus using these borrowed pieces of information to form who they are. these pieces are added to previously installed programming which was applied by parental units. the synthesis of all of this information helps us to structure an image of our being and our world view, based on internal conjecture which is influenced by external stimuli.
since this is happening over time and involves a great deal of grey matter processing, apparently we don't notice this. of course, this is just my opinion.
