⊿ Point. {R} Glossary. ◢ Keyword: D. ◥ University. {q} PhD. {tr} Training. ⚫ UK. ↂ EndNote. ☢️ C' Laws. ☝️ Weerakkody. ☝️ [BS] Heigham. Deductive reasoning. Deductive reasoning links premises with conclusions. If all premises are true, the terms are clear, and the rules of deductive logic are followed, then the conclusion reached is necessarily true. Deductive reasoning (top-down logic) contrasts with inductive reasoning (bottom-up logic) in the following way: In deductive reasoning, a conclusion is reached reductively by applying general rules that hold over the entirety of a closed domain of discourse, narrowing the range under consideration until only the conclusion(s) is left. In inductive reasoning, the conclusion is reached by generalizing or extrapolating from, i.e., there is epistemic uncertainty. Note, however, that the inductive reasoning mentioned here is not the same as induction used in mathematical proofs – mathematical induction is actually a form of deductive reasoning.
Simple example[edit] An example of a deductive argument: All men are mortal.Socrates is a man.Therefore, Socrates is mortal. Law of detachment[edit] P → Q. Deductive Reasoning Versus Inductive Reasoning. In science, there are two ways of arriving at a conclusion: deductive reasoning and inductive reasoning. Deductive Reasoning Deductive reasoning happens when a researcher works from the more general information to the more specific. Sometimes this is called the “top-down” approach because the researcher starts at the top with a very broad spectrum of information and they work their way down to a specific conclusion. For instance, a researcher might begin with a theory about his or her topic of interest. From there, he or she would narrow that down into more specific hypotheses that can be tested. An example of deductive reasoning can be seen in this set of statements: Every day, I leave for work in my car at eight o’clock. The deductive statement above is a perfect logical statement, but it does rely on the initial premise being correct.
Inductive Reasoning Inductive reasoning works the opposite way, moving from specific observations to broader generalizations and theories. References. Deduction & Induction. In logic, we often refer to the two broad methods of reasoning as the deductive and inductive approaches. Deductive reasoning works from the more general to the more specific. Sometimes this is informally called a “top-down” approach. We might begin with thinking up a theory about our topic of interest. We then narrow that down into more specific hypotheses that we can test. We narrow down even further when we collect observations to address the hypotheses. This ultimately leads us to be able to test the hypotheses with specific data – a confirmation (or not) of our original theories.
Inductive reasoning works the other way, moving from specific observations to broader generalizations and theories. These two methods of reasoning have a very different “feel” to them when you’re conducting research. Category:Theories of deduction. {th} *Scientific. {th} *Philosophical.