A friend of mine just quit hu's doctoral program, just before hu's defense. The reason:
Friend had made a significant and very important discovery in hu's field and made that the centrepiece of hu's dissertation and research program. One week before hu's defense, hu was reading a journal in the language of the country where the material which the dissertation research was focused on (dissertation was in english, though) and there on the page was the same very important discovery (it had the nature of discovering something in the history of the discipline in that country). Friend couldn't see how hu could defend hu's dissertation honestly as a very significant discovery, since someone else had made that discovery at the same time as hu, but had published it before hu.
Starting all over was not an option for friend as hu had taken eight years to do the research. Cancelling the defense, of course, was an option. But then what?
What would you do if you were me and heard this story? if you were the friend?
If I was the friend, at my defense I would say:
"Coincidentally and independently, Professor Smartypants at Dingo University made the same discovery that I dod of Iron Age basketweaving techniques in Atlantis by studying smoke signals. My own independent discovery confirms Smartypants's."
I don't see the problem, but like others I suspect more is going on. The only justifiable reasons to quit a ph.d. that I can think of are:
1. Ethics (e.g., your supervisor kills pandas)
2. Money (e.g., the university suddenly raised tuition by 500% and cut your funding)
3. Personal reasons (e.g., my home town is about to be obliterated by a meteor so I need to go with Bruce Willis to destroy it)
