It’s always more sad than disappointing to see a hero fall. Koreans were thrilled when taekwondo master Moon Dae-sung won a gold medal with a spectacular roundhouse kick in the 2004 Athens Olympics.

The athlete-turned-professor-turned-aspiring lawmaker is in trouble: He is suspected of plagiarizing his doctoral, and possibly master’s, theses. Despite Moon’s denial, there appears even no need for more debate, as his papers copied dozens of pages, even including typos, belonging to someone else.

Plagiarism itself makes little stir in Korea, where more than half of Presidential nominees for Cabinet ministers have a record or two of pirating other people’s theses. The time has long past for the nation to do away with this collective betrayal of conscience.

Moon should withdraw his candidacy. Coincidentally or not, Hungarian fencing hero-turned-President Pal Schmitt, possibly Moon’s role model, quit his job for exactly the same reason Monday, citing his nation’s unity.

It will take only a few months for Kookmin University, which conferred the doctorate, to decide whether to nullify it or not. Voters can give their verdict even before then, in next week’s elections.

But Moon’s reason for quitting should not necessarily be for the nation, much less for his Saenuri Party or the International Olympic Commission, of which he is a member. It’s because the days he will have to live are far longer than those he has lived for this 38-year-old. A lifelong career cannot be built on deception.

The plagiarism was a roundhouse kick to those who love his fair play and sportsmanship.