Membro Diamond

Stupidity is a more dangerous enemy of the good than malice. Evil always carries within itself the germ of its own subversion in that it leaves behind in human beings at least a sense of unease. Against stupidity we are defenseless.  

Stupidity is, in essence, not an intellectual defect but a moral one.  The impression one gains is that, under certain circumstances, people are made stupid or that they allow this to happen to them.  The stupid are deprived of their inner independence, and, more or less consciously, give up establishing an autonomous position. The fact that the stupid person is often stubborn must not blind us to the fact that he is not independent. In conversation with him, one virtually feels that one is dealing not at all with a person, but with slogans, catchwords and the like that have taken possession of him. He is under a spell, blinded, misused, and abused in his very being. Having thus become a mindless tool, the stupid person will also be capable of any evil and at the same time incapable of seeing that it is evil. 

- Dietrich Bonhoeffer