I can't think of a decent thesis on Eternal Sunshine of the Spotless Mind.To me it seems as if Clementine & Joel's destiny is to meet again, they...

I love this film! What a great question you have to do!
Well, just a few suggestions to help you along then. I guess the crux of the film is
about wiping out our memories. Can we really change our destiny if we forget about
someone completely? The case in point is Kirsten Duntz's character, who ends up having
another relationship with the Doctor, even though she has had her memories erased once.
It appears that the message of the film is about the danger of playing with memory - we
can't change our destiny it appears by erasing certain parts of our lives, and the film
suggests it is actually dangerous to do so. Part of being human is coping with the pain
and the hurt of events when we would rather forget they ever happened. Hope that
helps!