ABSTRACT
Migration is a bewildering set of processes to understand, and there is no shortage of theories to explain why and where people migrate. Exploring theories should be more than just an academic exercise, however. Understanding why people migrate may point to processes of global structural inequalities and disadvantage that warrant our attention. A key theoretical issue then is that the explanation of migration may be different for different (groups of ) people over time and space. This in turn suggests that an overarching theory of migration is an impossibility, or at least too abstract as a lens on the variety of migrations that have occurred across the world and throughout history (e.g. Brettell and Hollifield, 2008). One helpful way through the range of explanations is to distinguish, as Massey et al. (1998) do, between theories that explain the creation or the initial phase of a particular migration, and theories that explain subsequent phases, that is the ‘continuation’ or the ‘path dependency of migration systems’ (Collyer, 2005, 700). No doubt, this distinction has value, but in practice what initiates and continues different forms of migration overlap. Boyle, Halfacree and Robinson (1998) offer another distinction, between determinist theories (theories that on their own determine migration behaviour and patterns) and integrative theories (theories that bring together different theoretical and conceptual propositions). This
distinction has merit too, but often so-called determinist arguments integrate a number of different political, cultural, economic, environmental and social processes, and integrative theories can be remarkably determinist. I would add to this that we can delineate between explanatory and critical theories, though what exactly constitutes ‘critical’ is not always clear. As a consequence of the limitations of these various distinctions, we are faced with a dilemma: how to make migration comprehensible? While I discuss whether certain theories seem to be primarily concerned with the initiation or continuation of migration, and whether they are explanatory or critical, I have organized my discussion of the various theoretical approaches around Boyle et al.’s framework. I do this because they focus on the socio-theoretical foundations of the theory involved, rather than on often thorny assumptions about when and how a particular migration began and/or continued, or indeed whether the theory is in fact critical.
