The eighteenth-century German physicist, wit and philosopher Georg Christoph Lichtenberg described his philosophy as “a doctrine of scattered occasions”. It would be dishonest – as well as pointless, because no one would be deceived – to pretend that this collection of essays is anything other than the product of scattered occasions. With few exceptions, the pieces were all in some sense commissioned. They began as lectures, reviews and editorials, or as my regular contributions to Philosophy Now.

One of the exceptions is the title essay “Reflections of a Metaphysical Flâneur”, which I hope will be read as an overture. Some of the themes that appear in subsequent pages are sounded, although sometimes in a different guise. The essay is in part the expression of a lifelong love affair with a story by Robert Walser – The Walk – although readers familiar with Jean-Paul Sartre's incomparable philosophical novel Nausea will see the ghost of Antoine Roquentin accompanying the Flâneur on parts of his walk. It is an attempt at a mode of philosophical writing that fuses vision and argument, reminiscence and description, and something not far from grumbling. It is a foretaste of a book that has been in progress for over a quarter of a century – De Luce – which I promised myself to finish by the end of the millennium. Wisely, I did not specify which millennium.

The remaining essays look backwards and forwards.