A man must be excessively stupid, as well as uncharitable, who believes there is no virtue but on his own side.

Believing that decency exists only on your side of a disagreement takes both unkindness and a failure to look. People arrive at different conclusions from different experiences, and almost all of them are trying to protect something reasonable. Denying that is comfortable, because it turns a difficult argument into a simple one. It also guarantees you will never understand why you are losing it.

Pick the position you find hardest to respect and find the honest version of it, held by a decent person. You do not have to agree, but you should be able to state it in a way they would accept.