I really detest slippery slope fallacies. Examples: If we legalize marijuana then it will lead to the legalization of harder drugs down the road like cocaine and heroin. If we allow gays to marry, then nothing would keep us from legalizing polygamy and incest. If we allow prayer in this school, then it will eventually mean the complete break down of the separation of church and state. They are easy enough to rebuke because you only have to ask for proof that one event will follow from another. What evidence can you provide that shows legalizing marijuana will lead to the legalization of other controlled substances? What evidence can you provide that shows allowing gays to marry will lead to polygamy or incest? What evidence can you provide that shows that prayer in school has ever lead to a complete break down between church and state? In all three of these cases, there is actually evidence that argues the alternative point of view? Do these annoy anyone else as much as they annoy me? I find them incredibly unintelligent, but I am surprised how often they are used in the media and by politicians.