Abstract

Rudolf Carnap proposed three reduction rules to improve scientific language. Those rules indicate when it is correct to add a property in situations in which other properties are already had. Assuming the theory of mental models, it has been shown that the rules are not hard to use from the cognitive point of view. The key to argue that is to accept that the human mind works as dual-process theories claim. According to these theories, people can use two different systems. One of them implies effort but the other one does not. Thus, the idea is that Carnap’s reduction rules can be applied resorting just to the system not implying cognitive effort. This paper goes one step further and poses that even from a Popperian perspective the reduction rules keep not being difficult. One might think that falsifiability requires cognitive effort because it needs to address situations in which the sentences are false. However, this paper tries to explain that, following the theory of mental models, that is not hard if the sentences are conditionals, and the sentences in the reduction rules have conditional structures.