Readers of Philosophy don't need to be reminded of the importance of David Wiggins's contribution to philosophy. As Christopher Peacocke puts it in his personal-philosophical memoir published in this issue, Wiggins's philosophy sets new questions – yet his own answers are always framed as extensions or elaborations ‘of what we should preserve and recognize in the writings of great thinkers in the history of philosophy’. The significance and originality of his work have been recognised in the many accolades he has received during his long career. He was elected a Fellow of the British Academy in 1978, when he was in his mid-forties. An International Honorary Member of the American Academy of Arts and Sciences since 1992, he became Wykeham Professor of Logic at Oxford two years later, an event (along with his sixtieth birthday) that was marked by a collection of essays with replies, edited by Sabina Lovibond and S.G. Williams (Blackwell, 1996), and he was President of the Aristotelian Society for 1999-2000. It is an honour and a pleasure to expand these accolades with this issue of Philosophy which, in his ninetieth year, is wholly devoted to his work. The five central essays span the areas of philosophy that have particularly concerned him throughout his career: from philosophical logic, philosophy of language, and metaphysics, to ethics and social and political philosophy.

In ‘A Sensible Pragmatist Conception of Truth’ Cheryl Misak traces the pragmatist elements in Wiggins's ‘marks-of-truth’ view. In particular, her central suggestion is that his distinctive use of pragmatist ideas facilitates the reconciliation of elements of subjectivism with a proper recognition of the objectivity of truth. Ian Rumfitt's ‘Truth, Marks of Truth, and Conditionals’ continues the focus on truth by proposing refinements, qualifications, and a shift of emphasis in relation to Wiggins's marks of truth-elucidation in his 2002 paper ‘An Indefinibilist Cum Normative View of Truth and the Marks of Truth’. Rumfitt develops ideas from F.P. Ramsey's posthumously published book On Truth, in preference to Wiggins's reliance on Alfred Tarski, and he seeks to replace Wiggins's mark of convergence with a condition drawn from Frege concerning the public character of sense.

‘Wiggins on Ethical Objectivism and “Des Cannibales”’, by Adam Etinson, continues the discussion of Wiggins's combination of a sensible subjectivism with the objectivity of truth in the particular domain of ethics. The paper is a sympathetic critical reconstruction of his development of this position in the light of J.L Mackie's two famous arguments for an error theory of moral judgement. Etinson elaborates the position, while questioning some of its aspects, by attempting to answer such questions as: What does Wiggins accept in Mackie's arguments? How does he combine this with rejecting Mackie's conclusion? And how exactly should we understand the objectivism that Wiggins proposes instead?

Wiggins's sceptical engagement with the dominant economic approach to environmental policymaking – in particular his views on sustainability, needs, and the proper constraints upon economic reasoning – is sympathetically elaborated in John O'Neill's ‘Ethics, Economics, and Sustainability’. Closely related themes are pursued in Jeff Seidman's ‘Respect for Nature, Respect for Persons, Respect for Value’, especially those elaborated in Wiggins's ‘Nature, Respect for Nature, and the Human Scale of Values’. Seidman's aim is to present a direct argument for Wiggins's conception of nature as a proper object of our respect, in the sense that we are bound in our practical reasoning to recognize the limitation that it imposes on our will. Although the argument is constructed from Wiggins's own materials, it departs from his conception in stressing a greater continuity between the respect we owe both to nature and to persons and other objects or systems of value generally. We are delighted that Professor Wiggins has contributed illuminating and incisive individual replies to these specially commissioned papers.

The breadth and depth of the discussions, and the way they are embedded in the history of philosophy, reflect the perspicacity, richness and agility of Wiggins's mind. Together with some other of his philosophical virtues, notably his ‘intellectual empathy’, these are strikingly illustrated in Christopher Peacocke's opening piece, ‘David Wiggins: Personal Philosophical Memoir’. Finally, our ‘reviews’ of three of Wiggins's collections of essays – Sophie-Grace Chappell on Needs, Values, Truth (1997-2002); Guy Longworth on Ethics. Twelve Lectures on the Philosophy of Morality (2006); and Jennifer Frey on Solidarity and the Root of the Ethical (2008) – confirm the immense achievement and lasting significance of David Wiggins, a real philosopher.