Natalia Żyluk, Mikołaj Michta & Mariusz Urbański (2017). Yet Another Shade of Deduction. On measuring deductive flexibility and how it may relate to other cognitive abilities, Logic and Logical Philosophy, DOIDFT has been developed to account empirically for different ways of understanding the concept of deduction in psychological vs logical traditions. In DFT items the task is to choose all and only these combinations of premises which justify the conclusion. Solving this kind of problem requires deductive reasoning skills as well as specific kind of “flexibility”, understood as the ability to switch between different sets of premises that potentially entail a given conclusion and to think about multiple sets of premises simultaneously. In order to grasp the cognitive characteristics highlighted above, we propose the notion of deductive flexibility. We developed Deductive Flexibility Test: a reliable instrument which can be used for research purposes.