Michael Ramsden – Logic and Fallacies

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Michael Ramsden – Logic and Fallacies Logic and Fallacies Public Faith Conference February 16-17, 2018 Michael Ramsden A AMBIGUITIES Some statements are ambiguous. Phrasing or • If I make an exception for you then I have to make an punctuating them differently can land you with exception for everyone entirely different meanings. • Either dead people come back to life and are FALSE DICHOTOMIES married to the people they were married to before, This is where you’re presented with only two options, or there is no resurrection when actually more are available. • Have you stopped beating your wife? SLIPPERY SLOPE This reasoning aims to show that a particular proposition is unacceptable because of increasingly • “Here is this man performing many miraculous signs. unacceptable events. It can be used positively, to help If we let him go on like this, everyone will believe in one see where a particular line of reasoning may end him and then the Romans will come and take away up, but as a means of logic, it is fallacious. both our place and our nation.” John 11:47-8 B APPEAL TO FORCE • God could not possibly send my lovely granny to Hell “Anyone who does not agree with the new policy will be fired.” • The Jews had already agreed that if anyone should confess Jesus to be the Christ he should be put out APPEAL TO PITY of the Synagogue “You mean you don’t think this article is good? I spent so much time on it.” • How can you sentence this man to life in prison? Who will look after his wife and children? APPEAL TO CONSEQUENCES “If we allow these people to preach the gospel then our culture will be changed therefore we should not • It is better for one man to die than for a whole allow them to preach.” nation to perish. Therefore, we should kill Jesus. © Redeemer Churches & Ministries, 2017 LOGIC AND FALLACIES C CHARACTER ASSASSINATION • “Here is a glutton and a drunkard, a friend of tax This is when a person or group is attacked, rather collectors and sinners.” Matthew 11:19 than the proposition itself. • Christianity is irrelevant to life. APPEAL TO POPULARITY This is when something is argued to be true on the • That book was written by a left-wing hippy. You cannot basis that a large number of people hold to it. possibly take the ideas seriously. • How can millions of people be wrong in their sincere belief? HASTY GENERALISATIONS This is often used to write off a whole idea or practice by making assumptions about the whole from a • All Christians are superstitious. small sample set. • But Mum and Dad, everyone is doing it! D STRAW MAN • ”Christians eat the flesh and blood of their leader, A straw man is where a person makes a case much cannibalism is barbaric and wrong.” weaker than it actually is. It has to be said that Christians are often guilty of using this tactic against others, so we need to watch that. • ”You only say that because you are an evangelical.” GENETIC FALLACY This is the reasoning by which ideas or a people are • ”My car has been playing up and will not start. In rejected on the basis of their origin. frustration I kick the tire. Suddenly the car starts — therefore the tire-kicking caused the car to start.” THE POST HOC FALLACY This is where two events running in parallel are fallaciously seen as related casually. © Redeemer Churches & Ministries 2017 2.
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