In, The Groove Of Ashteroth, the inimitable Doug Wilson uses a new analogy to explain an old and tremendously frustrating problem:
Some create the leaven on purpose, others transmit it unknowingly, others yet are insufficiently on guard against it, some see a problem and raise a hue and cry against it in such a manner as to make themselves and all their friends ridiculous, and a mere handful see the problem, and fight it in all wisdom. . . .
It gets more difficult. As the leaven advances, this does create the hard evidence that has thus far been missing. But at the same time it simultaneously renders everyone incapable of seeing that evidence. . . .
Late in the process you are a voice crying in the asylum, where they locked you up for speaking the truth in irritating ways.