A proposition is claimed to be true or good solely because a majority or many people believe it to be so.
#1: Nine out of ten of my constituents oppose the bill, therefore it is a bad idea.
#2: Nine out of ten of my fellow congressmen favor the bill, therefore it is a good idea.
#3: Brand X vacuum cleaners are the leading brand in America. You should buy Brand X vacuum cleaners.
#4: Watch Show X – the #1 watched show on television!
#6: All of my friends are doing it.
#7: In a court of law, the jury vote by majority, therefore they will always make the correct decision.
#8: Everyone jaywalks here and as long as I look carefully, nothing will happen.
#9: Many people use agave nectar and believe it’s healthy, so it must be.
#10: Most dermatologists approve of and prescribe Accutane, so it must be safe.
#11: Many scientists say there isn’t a god of the universe, so there cannot be one.
Some information and examples taken/adapted from The Full Wiki
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