I see that Lillian Lee & her team at Cornell University have carried out some useful research on how to win arguments. Their key findings seem to include:

• Timing: the first person to reply has a better chance of changing the opinion of the original person;
• Alternative terminology: you’re better to use different words than those originally used e.g. if the original person says “climate change” then you talk about “global warming”;
• Calm language: this is better than swearing or aggressive terms;
• Length: longer replies are more persuasive;
• Evidence: using numbers and statistics to back up your argument is more convincing;
• Linking: cross refer to quotes and outside sources rather than just using quotes within your reply;
• Hedge your bets: hedges (such as “this could be the case“) are not weaker as you might expect but may actually make an argument easier to accept by softening the tone;
• Know when to give up: after 4 or 5 back-and-forth posts there is very little chance of changing anyone’s mind.