I've noticed, perhaps incorrectly, that many philosophers and ethicists regard logical coherence as an integral component of forming and defending moral positions. While I can understand why logical coherence would be necessary for, say, a scientist who is trying to describe how something works, I do not seem to see why logical coherence would be needed for ethics -- where, presumably, there are no objectively right or wrong answers.
Read another response by Eric Silverman, Peter Smith