The argument set out in this chapter is that personalisation technologies are fundamentally inimical to the way we have built our legal and political traditions: the building blocks, or the raw materials if you will, that make up the sources of the ‘self’. The advances in the use personalisation technologies and the implications for how we understand our political and social lives through law (constitutionalism) hinge on the importance of language and the risks posed by personalisation technologies to the building of personality and forms of social solidarities. This chapter explores the centrality of language to agency – how this relationship builds our legal and political traditions and the risks posed by personalisation technologies.