Editing Deductive reasoning (section)

==== Psychological theories of deductive reasoning ====
Various psychological theories of deductive reasoning have been proposed. These theories aim to explain how deductive reasoning works in relation to the underlying psychological processes responsible. They are often used to explain the empirical findings, such as why human reasoners are more susceptible to some types of fallacies than to others.<ref name="Schechter" /><ref name="Johnson-Laird2009" /><ref name="Johnson-Laird1993" />

An important distinction is between ''mental logic theories'', sometimes also referred to as ''rule theories'', and ''mental model theories''. ''Mental logic theories'' see deductive reasoning as a [[language]]-like process that happens through the manipulation of representations.<ref name="Schechter" /><ref name="Johnson-Laird2009" /><ref name="García-Madruga" /><ref name="Johnson-Laird1993">{{Cite journal |last1=Johnson-Laird |first1=Philip N. |last2=Byrne |first2=Ruth M. J. |year=1993 |title=Precis of Deduction |url=https://philpapers.org/rec/JOHPOD-2 |journal=Behavioral and Brain Sciences |volume=16 |issue=2 |pages=323–333 |doi=10.1017/s0140525x00030260|url-access=subscription }}</ref> This is done by applying syntactic rules of inference in a way very similar to how systems of [[#Natural deduction|natural deduction]] transform their premises to arrive at a conclusion.<ref name="Johnson-Laird1993" /> On this view, some deductions are simpler than others since they involve fewer inferential steps.<ref name="Schechter" /> This idea can be used, for example, to explain why humans have more difficulties with some deductions, like the [[modus tollens]], than with others, like the [[modus ponens]]: because the more error-prone forms do not have a native rule of inference but need to be calculated by combining several inferential steps with other rules of inference. In such cases, the additional cognitive labor makes the inferences more open to error.<ref name="Schechter" />

''Mental model theories'', on the other hand, hold that deductive reasoning involves models or [[mental representation]]s of possible states of the world without the medium of language or rules of inference.<ref name="Schechter" /><ref name="Johnson-Laird2009" /><ref name="Johnson-Laird1993" /> In order to assess whether a deductive inference is valid, the reasoner mentally constructs models that are compatible with the premises of the inference. The conclusion is then tested by looking at these models and trying to find a counterexample in which the conclusion is false. The inference is valid if no such counterexample can be found.<ref name="Schechter" /><ref name="Johnson-Laird2009" /><ref name="Johnson-Laird1993" /> In order to reduce cognitive labor, only such models are represented in which the premises are true. Because of this, the evaluation of some forms of inference only requires the construction of very few models while for others, many different models are necessary. In the latter case, the additional cognitive labor required makes deductive reasoning more error-prone, thereby explaining the increased rate of error observed.<ref name="Schechter" /><ref name="Johnson-Laird2009" /> This theory can also explain why some errors depend on the content rather than the form of the argument. For example, when the conclusion of an argument is very plausible, the subjects may lack the motivation to search for counterexamples among the constructed models.<ref name="Schechter" />

Both mental logic theories and mental model theories assume that there is one general-purpose reasoning mechanism that applies to all forms of deductive reasoning.<ref name="Schechter" /><ref name="García-Madruga">{{Cite journal |last1=García-Madruga |first1=Juan A. |last2=Gutiérrez |first2=Francisco |last3=Carriedo |first3=Nuria |last4=Moreno |first4=Sergio |last5=Johnson-Laird |first5=Philip N. |date=November 2002 |title=Mental Models in Deductive Reasoning |url=http://revistas.ucm.es/index.php/SJOP/article/view/SJOP0202220125A |journal=The Spanish Journal of Psychology |volume=5 |issue=2 |pages=125–140 |doi=10.1017/s1138741600005904 |pmid=12428479 |s2cid=15293848}}</ref><ref>{{Cite journal |last=Johnson-Laird |first=Philip N. |date=18 October 2010 |title=Mental models and human reasoning |journal=Proceedings of the National Academy of Sciences |volume=107 |issue=43 |pages=18243–18250 |doi=10.1073/pnas.1012933107 |issn=0027-8424 |pmc=2972923 |pmid=20956326 |doi-access=free}}</ref> But there are also alternative accounts that posit various different special-purpose reasoning mechanisms for different contents and contexts. In this sense, it has been claimed that humans possess a special mechanism for permissions and obligations, specifically for detecting cheating in social exchanges. This can be used to explain why humans are often more successful in drawing valid inferences if the contents involve human behavior in relation to social norms.<ref name="Schechter" /> Another example is the so-called [[Dual process theory|dual-process theory]].<ref name="Evans" /><ref name="Schechter" /> This theory posits that there are two distinct cognitive systems responsible for reasoning. Their interrelation can be used to explain commonly observed biases in deductive reasoning. System 1 is the older system in terms of evolution. It is based on associative learning and happens fast and automatically without demanding many cognitive resources.<ref name="Evans" /><ref name="Schechter" /> System 2, on the other hand, is of more recent evolutionary origin. It is slow and cognitively demanding, but also more flexible and under deliberate control.<ref name="Evans" /><ref name="Schechter" /> The dual-process theory posits that system 1 is the default system guiding most of our everyday reasoning in a pragmatic way. But for particularly difficult problems on the logical level, system 2 is employed. System 2 is mostly responsible for deductive reasoning.<ref name="Evans" /><ref name="Schechter" />