This study examined whether exchanging opinions affected teachers’ beliefs regarding corporal punishment. Participants were nursery and kindergarten teachers (n=100) as well as elementary school teachers (n=116) who attended in-service teacher training courses. Their opinions on the idea that “young children should never be physically punished under any circumstances” were explored before and after the discussion. A text-mining analysis was conducted to scrutinize the reasoning behind their opinions. Results showed that there was significant increase in the number of teachers who supported corporal punishment following the discussion. They stated that such action could not be avoided in some circumstances and justified it by concluding that “corporal punishment by parents may be needed to teach children to value their own and others’ lives.” To eradicate corporal punishment, we may have to provide teachers with opportunities to consider alternative methods of cultivating morality and prudence in children.