Words by Matt Beard – Philosopher at The Ethics Centre

There’s plenty of argument around – not all of it good. We see finger-pointing and name-calling but not many genuine attempts to understand someone else’s point of view. It makes for good television but is less great for a vibrant, productive democracy.

Fixing the standard of public debate is a massive challenge with no quick fixes. The least you can do is avoid being part of the problem. A first step is to know about ‘logical fallacies’ – signposts of poorly structured reasoning guarantee any conclusion you reach will be based on shaky evidence or argument. Try to avoid these five common ones next time you’re having an argument. Better still, spot how regularly you see them used by people who should know better – like politicians and public commentators.

Ad hominem: Remember poor old Duncan Storrar? He asked a question about tax rates on Q&A and was sledged in the media for the next three days for being a dole bludger and a drug user. Duncan was a victim of a classic logical fallacy, the ad hominem.

This is Latin for ‘to the person’. It’s when you attack a person instead of the argument they’re making. Not only is it rude, it doesn’t bring us any closer to the truth. Who you are doesn’t change the nature of what you’ve said, so in a debate it helps to focus on the content of the argument.

False cause: This happens when you assume two things are causally linked because one happened after the other when they could have been random and unrelated. The rise in global temperature correlates with the decrease in pirates in the world. Coincidence? I think not. A few more Jerry Bruckheimer films and we ought to fix global warming.

Assuming because something happens after something else it happened because of it is unfortunately pretty common. For example, when a previous government is blamed for current events – say, the economy – simply because the economic collapse happened after they came to power.

Tu quoque: Again with the Latin? This translates as “you too”. The tu quoque (pronounced too kwo-kway) fallacy looks exactly like it says on the box: it’s an appeal to hypocrisy. So instead of engaging with criticism levelled against you or your position, you point out the times your critics have also been guilty of the same mistakes. The best defence is a good offence, right?

Not this time. In this case, the argument falls down because hypocrites can still speak the truth. If a thief tells you it’s wrong to steal, he’s not wrong! Using his stealing to defend your stealing isn’t going to fly.

No True Scotsman: This fallacy comes from the Scottish example, ‘All Scots are brave and never flee battle’. ‘But MacDougall is a Scot and he fled yesterday!’ ‘Ah, but MacDougall isn’t a true Scot’. The No True Scotsman is a way of shifting the goal posts so contradictory evidence can’t actually disprove your claim.

When you make an argument like “all Australians believe in the value of mateship”, you would be proven wrong if you met an Australian who didn’t care much for mateship. The No True Scotsman fallacy is a way of trying to overcome that issue. Instead of losing the argument, you can simply reply “well, you’re not a true Australian”.

Straw man: Imagine beating up a scarecrow to show how tough you are. It’s an easy beat and it doesn’t really prove anything. The straw man fallacy is the debating version of boxing an inanimate object. It’s when you characterise your opponent’s argument in a way that’s more simplistic, unreasonable or outright ridiculous to win the argument. If what you’ve got to say is right, you should be able to prove it against the best form of the opposing argument.

Listen to the best form of the argument. Subscribe to The Ethics Centre’s IQ2 series in 2017. Four debates, no fallacies.