2 Opposing claims and evidence
The suggestion is that, as a first step, you look for supporting claims. You looked at an example and you may have found further supporting claims.
Now assume that you have exhausted your search. Before writing up your argument, you may want to pause. For any claim, it is usually possible to find some supporting claims. But what if there are also claims out there that contradict your main claim? Before you can make a judgement, you need to collect both supporting and, what we will call, opposing claims.