Explain the theme of destiny and self determination in "Oedipus the King" and "Othello."

The fate and free will is a powerful question in both
works.  I think that both works show that free will has limitations and that there are
other elements at play which tend to hamper full realization of individual autonomy. 
For Oedipus, this seems to be fairly clearly defined in that he seeks to outrun his own
destiny.  He believes that his use of freedom and clarity in judgment can overcome what
is fated to be.  In this light, one sees Oedipus as seeking to appropriate a domain that
is not his to control.  Eventually, he ends up paying dearly for this.  For Othello, I
think that the matter is a bit more muddled.  Shakespeare does not necessarily invoke
the fate condition to limit human freedom, but rather argues that there are other
factors perhaps within us that seem to curtail our own use of freedom.  The limiting
function is not outside the individual, but rather within them. When Iago suggests that
"Men should be what they seem," he is reflecting the duplicity that might exist in their
own use of freedom.  Their spirit of independence and autonomy might preclude them from
doing what makes them happy.   For Othello, jealousy and insecurity ends up hampering
his own attempts to be happy.  Iago knows and pinpoints his weaknesses of his love for
Desdemona, his "outsider" status as being reason why things won't work out, as well as
the basic idea that what he has done is not as important as the barriers which preclude
him from being embraced.  These elements are internal, and while their presence might be
there to some extent, the fact that Othello internalizes all of them and acts on all of
these impulses to end up undone by the end of the play suggests that Shakespeare's
conception of self determination is one that is fraught with its own self destructive
tendencies within it.