Deductive reasoning Warning: You are not logged in. Your IP address will be publicly visible if you make any edits. If you log in or create an account, your edits will be attributed to your username, along with other benefits.Anti-spam check. Do not fill this in! === Definitory and strategic rules === Rules of inferences are definitory rules: they determine whether an argument is deductively valid or not. But reasoners are usually not just interested in making any kind of valid argument. Instead, they often have a specific point or conclusion that they wish to prove or refute. So given a set of premises, they are faced with the problem of choosing the relevant rules of inference for their deduction to arrive at their intended conclusion.<ref name="Hintikka"/><ref name="BritannicaSystems">{{cite web |title=Logical systems |url=https://www.britannica.com/topic/logic/Logical-systems |website=www.britannica.com |access-date=4 December 2021 |language=en}}</ref><ref name="Pedemonte">{{cite journal |last1=Pedemonte |first1=Bettina |title=Strategic vs Definitory Rules: Their Role in Abductive Argumentation and their Relationship with Deductive Proof |journal=Eurasia Journal of Mathematics, Science and Technology Education |date=25 June 2018 |volume=14 |issue=9 |pages=em1589 |doi=10.29333/ejmste/92562 |s2cid=126245285 |url=https://www.ejmste.com/article/strategic-vs-definitory-rules-their-role-in-abductive-argumentation-and-their-relationship-with-5539 |language=english |issn=1305-8215|doi-access=free }}</ref> This issue belongs to the field of strategic rules: the question of which inferences need to be drawn to support one's conclusion. The distinction between definitory and strategic rules is not exclusive to logic: it is also found in various games.<ref name="Hintikka"/><ref name="BritannicaSystems"/><ref name="Pedemonte"/> In [[chess]], for example, the definitory rules state that [[Bishop (chess)|bishops]] may only move diagonally while the strategic rules recommend that one should control the center and protect one's [[King (chess)|king]] if one intends to win. In this sense, definitory rules determine whether one plays chess or something else whereas strategic rules determine whether one is a good or a bad chess player.<ref name="Hintikka"/><ref name="BritannicaSystems"/> The same applies to deductive reasoning: to be an effective reasoner involves mastering both definitory and strategic rules.<ref name="Hintikka"/> Summary: Please note that all contributions to Christianpedia may be edited, altered, or removed by other contributors. If you do not want your writing to be edited mercilessly, then do not submit it here. You are also promising us that you wrote this yourself, or copied it from a public domain or similar free resource (see Christianpedia:Copyrights for details). Do not submit copyrighted work without permission! Cancel Editing help (opens in new window) Discuss this page