If we’re all going to be disagreeing more, we should be careful to do it well. What does it mean to disagree well? Most readers can tell the difference between mere name-calling and a carefully reasoned refutation, but I think it would help to put names on the intermediate stages. So here’s an attempt at a disagreement hierarchy:

Truly refuting something requires one to refute its central point, or at least one of them. And that means one has to commit explicitly to what the central point is. So a truly effective refutation would look like:

The author’s main point seems to be x. As he says:

<quotation>

But this is wrong for the following reasons…

The quotation you point out as mistaken need not be the actual statement of the author’s main point. It’s enough to refute something it depends upon

–Paul Graham