Daniel Dennett in The Observer:
Just how charitable are you supposed to be when criticising the views of an opponent? If there are obvious contradictions in the opponent's case, then you should point them out, forcefully. If there are somewhat hidden contradictions, you should carefully expose them to view – and then dump on them. But the search for hidden contradictions often crosses the line into nitpicking, sea-lawyering and outright parody. The thrill of the chase and the conviction that your opponent has to be harbouring a confusion somewhere encourages uncharitable interpretation, which gives you an easy target to attack.
But such easy targets are typically irrelevant to the real issues at stake and simply waste everybody's time and patience, even if they give amusement to your supporters. The best antidote I know for this tendency to caricature one's opponent is a list of rules promulgated many years ago by social psychologist and game theorist Anatol Rapoport.
How to compose a successful critical commentary:
1. Attempt to re-express your target's position so clearly, vividly and fairly that your target says: “Thanks, I wish I'd thought of putting it that way.”
2. List any points of agreement (especially if they are not matters of general or widespread agreement).
3. Mention anything you have learned from your target.
4. Only then are you permitted to say so much as a word of rebuttal or criticism.
One immediate effect of following these rules is that your targets will be a receptive audience for your criticism: you have already shown that you understand their positions as well as they do, and have demonstrated good judgment (you agree with them on some important matters and have even been persuaded by something they said). Following Rapoport's rules is always, for me, something of a struggle…
More here.