It is sometimes said that philosophy begins with curiosity; but it would be as true to say that it starts in confusion (where any particular enquiry ends up depends on the gifts of those involved). Typically one finds oneself faced with a conflict between experience and reflection, or within thought itself. Certain things seem obviously morally impermissible say, but it appears impossible to conceive how anything could be, in and of itself, always and everywhere absolutely wrong. Justice seems to require redistributing wealth for the sake of welfare, yet compulsory taxation can also appear a paradigm of injustice: state-organised theft. Society represents itself as a voluntary association of free individuals, yet our sense of ourselves as voluntary agents is something formed by society not something antecedent that we bring to it.

So it continues. Natural rights may be as Bentham suggested ‘nonsense on stilts’, yet the liberal, political sensibility that he did much to form, finds ‘rights’ talk not just convenient but compelling.