When we form arguments or examine others’ arguments, we need to be cognizant of possible fallacies. A fallacy can be defined as a flaw or error in reasoning. At its most basic, a logical fallacy refers to a defect in the reasoning of an argument that causes the conclusion(s) to be invalid, unsound, or weak. The existence of a fallacy in a deductive argument makes the entire argument invalid. The existence of a fallacy in an inductive argument weakens the argument but does not invalidate it.
It is important to study fallacies so you can avoid them in the arguments you make. Studying fallacies also provides you with a foundation for evaluating and critiquing other arguments as well. Once you start studying and thinking about fallacies, you’ll find they are everywhere. You could say that we live in a fallacious world!
A fallacy exists because of an error in the structure of the argument. In other words, the conclusion doesn’t follow from the premises. Fallacies are specific types of non sequiturs, or arguments in which the conclusions do not follow from the premises. Other fallacies occur because of an error in reasoning. These are identified through examining the structure of the argument, through analysis of the content of the premises. These will become clear as you examine different types of fallacies.