2024-08-2520:21 Status: …
Definition
A deductive argument is an orientation of premises that intends to guarantee the conclusion. Because these arguments aim to validate something with absolute certainty, if it is found to be remotely false (in premise or implication), then it is absolutely false: At best, a deductive argument is an absolute truth (valid), and at worst is absolutely false (invalid). These arguments can take different forms, for more see Argument forms
Flow of Argumentation
A deductive argument must also logically make sense, and not constructed of nonsequitors that do not necessarily entail the proposed conclusion. E.g. dogs can be black, cats can be white therefore the sky can be blue. Unless substantial empirical (inductive evidence) is provided or supplemented (also not deductive), then this is an invalid deductive argument because the premises do not imply/necessitate the conclusion proposed: There must be an if-then relationship between the premises and the conclusion. Validity preserves truth, so if a conclusion is wrong, a premise must be wrong.
Validity of Premises
Deductive arguments often work under the assumption that the premises are true: “e.g.: all birds have beaks; some cats are birds. So, some cats have beaks.” The second premise is false, yet the argument is valid. Contrarily, the premises can be true, but the conclusion may be false “e.g. Some Americans are women. Brad Pitt is an American. Therefore, Brad Pitt is a woman.” However, the conclusion, and premises may be true but not form a valid argument: “e.g. Some Americans work in the movie industry; Angelina Jolie is an American; Hence, Angelina Jolie works in the movie industry.” This is a cascade of coincidences not a valid deductive argument.
Soundness of an Argument
A sound argument is a valid argument in which all the premises are true. Valid + All Premises are True = Sound
Because validity preserves truth, if the premises of a deductive argument are true, then the argument is sound. “E.g. All collies are dog. All dogs are animals. So, all collies are animals.”
