Two solutions
1). World War it is a provable fact that war's are very effective method of mass population control. The intelligent ones are generally smart enough to rise high enough in the ranks so that they don't have to fight and get killed or the grunts that do survive are generally the ones smart enough to avoid getting themselves killed.
2). License, really the world we live in now people are either too stupid or too lazy to even try to do things themselves, believe me I deal with some of the stupidest laziest people you will ever meet on a daily basis. If you had to fill in a form and then officially go somewhere with it to get a license to breed the stupid lazy ones wouldn't be smart enough to fill in the forms and the lazy ones wouldn't be bothered to get their ass to the place where they would be given the license.
1). World War it is a provable fact that war's are very effective method of mass population control. The intelligent ones are generally smart enough to rise high enough in the ranks so that they don't have to fight and get killed or the grunts that do survive are generally the ones smart enough to avoid getting themselves killed.
2). License, really the world we live in now people are either too stupid or too lazy to even try to do things themselves, believe me I deal with some of the stupidest laziest people you will ever meet on a daily basis. If you had to fill in a form and then officially go somewhere with it to get a license to breed the stupid lazy ones wouldn't be smart enough to fill in the forms and the lazy ones wouldn't be bothered to get their ass to the place where they would be given the license.