Flaws in Arguments (1). Critical Thinking D Gray Feb 2007 Updated September 2009. Post Hoc fallacy. Post hoc ergo propter hoc “After this, therefore because of this.” X occurs before Y Therefore X is the cause of Y Causality Sequential Coincidence Superstition. Post Hoc fallacy.
Updated September 2009
Walking under a ladder …
Early to bed, early to rise, …
Lucky rabbit’s foot
Your sins will find you out.
Watching television gives you square eyes.
Watching violence on TV causes violence in young people.
My alarm goes off at 5 am and the Sun rises shortly afterwards. Therefore my alarm causes the sun to rise.
Good exam results lead to happiness.
Breaking a mirror leads to seven years bad luck.
Finding a four leaf clover brings good luck
A black cat crossing your path brings bad luck
In Copenhagen, in Denmark, some people believe that the more storks that nest in the city, the more human babies are born.
They point to the fact that during the 12 years following WW2, the more storks that nested in Copenhagen in the Spring, the more babies were born in the year.
Many people warned that the liberalisation of drink laws, which allowed pubs and clubs to extend drinking hours, would fuel disorder.
However, the few months after their introduction, serious violent crime has fallen 21% - and it is down twice that in some towns. Also, there were 14% fewer woundings in the same period.
This shows that the new licensing laws have resulted in less violent crime.
Write a short Ad hominem argument as to why:
Rejecting an argument because of what the person does, not because of the strength of the argument.
Seeking to retain the status quo
Staying out late
Speeding on a motorway
Everyone does it