The main aim of the book is to investigate how medieval theologians and philosophers of early modern period deal with the human emotions, in order to control, modify and even overcome them...Perler's thesis is that there are important points of correspondence between medieval, modern and contemporary speculations despite the apparent differences. For example, Thomas Aquinas, Ockham, Descartes and Spinoza unanimously agree, as do many present-day philosophers, that emotions are not simply feelings, but states with a cognitive content. This is why emotions can be modified and influenced by other cognitive states.