I'm not sure what you mean to imply with your comment, but since someone had downvoted lukeprog's quote, I guess at least that person might have taken it to undermine Mencken's words. However, all Mencken is saying is that

p(easy,neat,plausible,wrong) > 0

which in no way contradicts

p(easy,neat,plausible,right) > 0.

Of course the essence of the quote is that a solution's being easy, neat and plausible doesn't imply it's right which often seems to be forgotten in public discourse.