Arguing is the new buzz in brainstorming. It’s an unsurprising backlash to the the brainstorm de rigueur of the past few years in which criticism is minimized. But its not an either/or decision. Both approaches are helpful depending on your needs at the moment.
Do you have a shortage of ideas? Use a brainstorm to generate fresh perspectives and potential connections. Have an abundance of ideas and need to filter them down? Invite someone to help you punch holes in the various ideas. It doesn’t need to be an argument. In fact, I suggest taking turns attacking and defending the various ideas on the table so you have to evaluate both the positive and negative qualities of a given idea. Call it an empathy exercise.
This also produces interesting results if you’re at a creative impasse. It takes a strong person to say, “Okay, for the moment let’s switch positions and I’ll argue for your idea and you try to attack it.”