 The study of arguments and argumentation is also closely connected to the study of reasoning, understood as the process of reaching conclusions on the basis of careful, reflective consideration of the available information, i.e., by an examination of reasons. According to a widespread view, reasoning and argumentation are related (as both concern reasons) but fundamentally different phenomena: reasoning would belong to the mental realm of thinking—an individual inferring new information from the available information by means of careful consideration of reasons—whereas argumentation would belong to the public realm of the exchange of reasons, expressed in language or other symbolic media and intended for an audience. However, a number of authors have argued for a different view, namely that reasoning and argumentation are in fact two sides of the same coin, and that what is known as reasoning is by and large the internalization of practices of argumentation (MacKenzie 1989; Mercier &amp; Sperber 2017; Mercier 2018). For the purposes of this entry, we can assume a close connection between reasoning and argumentation so that relevant research on reasoning can be suitably included in the discussions to come.