Introduction

Political constructivism is a theory that has developed comparatively recently which is centred on a set of ideas primarily about the justification of principles of political justice, and so also about justifying political actions and institutions. Everyday, we find ourselves in situations that require us to justify principles and our actions, either to others or to ourselves. We are faced with questions such as ‘Why did you do that?’ or ‘Was that the right thing for me to do?’ or ‘Should we have treated those other people in the way that we did?’ These questions demand answers that attempt to make transparent the reasons for our actions and principles. In addition, these answers often make claims about what reasons other people have or should recognize. The answers that we give in this questioning process might themselves be open to question, and these further answers may in turn be worthy of examination. A key question for justification is to ask whether this regress of questions ever comes to an end or are our reasons subject to an infinite regress of questions and answers and questions again. Justification is usually taken to consist in identifying the stopping point, or foundation, of such a regress, the ‘unmoved mover’ that anchors a chain of reasons.1 This foundational reason is regarded as an ‘unjustified justifier’ that necessarily occupies a position of authority in justificatory argument and is therefore the ground of our reasons and justifications.2 Identifying a foundational reason prevents further questioning and underpins the authority and objectivity of our reasons and principles.