Transfer of non-logical tendencies to formal reasoning

Previous psychological studies have shown that people are prone to systematic errors and biases when reasoning about natural language statements connected by logical operators such as: if, and, or, not, all and every. In the software engineering community, the use of formally defined notations based upon mathematical systems of logic are starting to gain favour over natural language based methods and it is generally believed that these will lead to improved reasoning. Although many formal notational constructs appear to share logical similarities with their natural language counterparts, they do not appear to be psychologically equivalent. This report describes a series of investigations aimed at determining whether people are inclined to use the same cognitive processes to reason about logical arguments irrespective of their linguistic context, and whether certain non-logical tendencies are ubiquitous across linguistic domains. in view of the fact that formal notations are commonly used for the development of safety-critical systems, this possible transfer of erroneous reasoning processes constitutes a genuine area for concern because developers who are unable to interpret or reason clearly about system specifications are likely to make the types of erroneous development decisions which have previously led to the production of defective systems.