The aim of this book, as described the Introduction, is to develop a psychologically informed progressive vision. I want to show how we can envision society, and the people and relationships within it, if we integrate psychology into a progressive commitment to equality and social justice.

To begin this journey, I want to discuss the development of the socialist humanist tradition. Socialist humanism was an international movement of intellectual thought – and, to some extent, activism – that advocated a psychological, humanistic reading of the works of the German philosopher and social activist, Karl Marx. The current book is by no means just for Marxists, and there are several ways in which the analysis to be developed in this book will differ from a classic socialist humanist stance. Nevertheless, I wanted to begin with a critical presentation of socialist humanism. This is for several reasons. First, it shows the depth, richness, and complexity of analysis that can be achieved by integrating humanistic psychology ideas into a progressive political base. It paints a powerful and compelling – albeit, at times, problematic – picture of how society, and the people within it, can be seen to function. Second, and closely related, it shows how a progressive perspective as radical as Marxism can, in fact, be understood in a way that is highly compatible with humanistic ideals and psychological beliefs. Third, a discussion of socialist humanism provides a means of introducing, and showing the radical foundations for, several of the key principles in the present text. Indeed, the perspective developed in this book could be considered a modified, contemporary version of socialist humanism. Fourth, a discussion of the limitations of socialist humanism helps to identify some of the pitfalls that a psychologyinformed progressivism can fall into, signposting ways towards a more genuinely egalitarian and humanistic vision. Fifth, along the lines of Mason,1 I have a desire to show the ongoing relevance of Marx's writings to contemporary progressive philosophy and politics. Maybe it is my father's bust of Marx on my bookshelves, but I am continually astounded by the depth and far-sightedness of his insights – psychologically as well as philosophically. Finally, my hope is that this chapter will whet the reader's appetite for the rest of this book by stimulating reflection on a range of key issues at the psychology– politics interface.