In this chapter, I will discuss two psychological experiments that challenge the view that people have an inbuilt ability to perform abstract logical reasoning. The first of these experiments, the “selection task”, has been widely interpreted as showing that, instead of logic, people use specialised procedures for dealing with problems that occur commonly in their environment. The second, the “suppression task”, has been interpreted as showing that people do not reason using rules of inference, like forward and backward reasoning, but instead construct a model of the problem and inspect the model for interesting properties. I will respond to some of the issues raised by these experiments in this chapter, but deal with them in greater detail in Chapter 16, after presenting the necessary background material.