ad hominem: Latin for "to the man." An arguer who uses ad hominems attacks the person instead of the argument. Whenever an arguer cannot defend his position with evidence, facts or reason, he or she may resort to attacking an opponent either through: labeling, straw man arguments, name calling, offensive remarks and anger. appeal to ignorance (argumentum ex silentio) appealing to ignorance as evidence for something. (e.g., We have no evidence that God doesn't exist, therefore, he must exist. Or: Because we have no knowledge of alien visitors, that means they do not exist). Ignorance about something says nothing about its existence or non-existence. argument from omniscience: (e.g., All people believe in something. Everyone knows that.) An arguer would need omniscience to know about everyone's beliefs or disbeliefs or about their knowledge. Beware of words like "all," "everyone," "everything," "absolute." appeal to faith: (e.g., if you have no faith, you cannot learn) if the arguer relies on faith as the bases of his argument, then you can gain little from further discussion. Faith, by definition, relies on a belief that does not rest on logic or evidence. Faith depends on irrational thought and produces intransigence. appeal to tradition (similar to the bandwagon fallacy): (e.g., astrology, religion, slavery) just because people practice a tradition, says nothing about its viability. argument from authority (argumentum ad verecundiam): using the words of an "expert" or authority as the bases of the argument instead of using the logic or evidence that supports an argument. (e.g., Professor so-and-so believes in creation-science.) Simply because an authority makes a claim does not necessarily mean he got it right. If an arguer presents the testimony from an expert, look to see if it accompanies reason and sources of evidence behind it. Appeal to consequences (argumentum ad consequentiam): an argument that concludes a premise (usually a belief) as either true or false based on whether the premise leads to desirable or undesirable consequences. Example: some religious people believe that knowledge of evolution leads to immorality, therefore evolution proves false. Even if teaching evolution did lead to immorality, it would not imply a falsehood of evolution. argument from adverse consequences: (e.g., We should judge the accused as guilty, otherwise others will commit similar crimes) Just because a repugnant crime or act occurred, does not necessarily mean that a defendant committed the crime or that we should judge him guilty. (Or: disasters occur because God punishes non-believers; therefore, we should all believe in God) Just because calamities or tragedies occur, says nothing about the existence of gods or that we should believe in a certain way. argumentum ad baculum: An argument based on an appeal to fear or a threat. (e.g., If you don't believe in God, you'll burn in hell) argumentum ad ignorantiam: A misleading argument used in reliance on people's ignorance. argumentum ad populum: An argument aimed to sway popular support by appealing to sentimental weakness rather than facts and reasons. bandwagon fallacy: concluding that an idea has merit simply because many people believe it or practice it. (e.g., Most people believe in a god; therefore, it must prove true.) Simply because many people may believe something says nothing about the fact of that something. For example many people during the Black plague believed that demons caused disease. The number of believers say nothing at all about the cause of disease. begging the question (or assuming the answer): (e.g., We must encourage our youth to worship God to instill moral behavior.) But does religion and worship actually produce moral behavior? circular reasoning: stating in one's proposition that which one aims to prove. (e.g. God exists because the Bible says so; the Bible exists because God influenced it.) composition fallacy: when the conclusion of an argument depends on an erroneous characteristic from parts of something to the whole or vice versa. (e.g., Humans have consciousness and human bodies and brains consist of atoms; therefore, atoms have consciousness. Or: a word processor program consists of many bytes; therefore a byte forms a fraction of a word processor.) confirmation bias (similar to observational selection): This refers to a form of selective thinking that focuses on evidence that supports what believers already believe while ignoring evidence that refutes their beliefs. Confirmation bias plays a stronger role when people base their beliefs upon faith, tradition and prejudice. For example, if someone believes in the power of prayer, the believer will notice the few "answered" prayers while ignoring the majority of unanswered prayers (which would indicate that prayer has no more value than random chance at worst or a placebo effect, when applied to health effects, at best). confusion of correlation and causation: (e.g., More men play chess than women, therefore, men make better chess players than women. Or: Children who watch violence on TV tend to act violently when they grow up.) But does television programming cause violence or do violence oriented children prefer to watch violent programs? Perhaps an entirely different reason creates violence not related to television at all. Stephen Jay Gould called the invalid assumption that correlation implies cause as "probably among the two or three most serious and common errors of human reasoning"