Before we discuss your book choices, could you explain what you mean by ‘the philosophical stakes of art’?

I’ve been deeply interested in the relation between art and philosophy for many years. My most sympathetic and engaged readers include a number of philosophers. They tend to be supportive of what I do, which is not always the case with art historians. I believe that art, and modern art in particular, does a great deal of philosophical work. The kind of reflection that takes place in philosophy carries on elsewhere in the culture, and very significantly in art. My interests have always crossed between art and philosophy, without ever leaving historical thinking behind.

Your first author, Denis Diderot, seems to share that point of view.

Yes, Diderot is a great philosopher and arguably the best-ever art critic. My own work as an art historian has engaged closely with his, especially Salons (the art-critical texts) and his related writings on painting and the stage. In my early book, Absorption and Theatricality: Painting and Beholder in the Age of Diderot, I discovered something about Diderot previously not recognised: the importance he placed on the relation between the painting and the viewer. That issue was also central to the development of French painting in the mid-18th century – between Chardin and Greuze – and Manet and his generation over 100 years later.

It’s a topic with resonance beyond the modern period. The basic idea is that painters inevitably construct a certain sort of relationship with the viewer. In the 1750s, Diderot put forward a set of claims as to how that relationship was supposed to work for a painting to be successful. I argue in my book that those claims and imperatives turned out to be foundational for modern painting and modern art generally.

This relationship between viewer and art continues with your second book, Maurice Merleau-Ponty’s Phenomenology of Perception.

Yes. Merleau-Ponty was a French philosopher from the 40s and 50s, a contemporary of Sartre and De Beauvoir. I read him for the first time in my early 20s before his works were translated. He represents so-called ‘existential phenomenology’. Of fundamental importance to him was that we are ‘embodied’ creatures, not disembodied perceptual systems and free-floating intelligences. He understood painting to be involved in a network of relations in which embodiment is crucial to the creation and experience of the work.

Why does he consider embodiment so important?

He takes it to be a fundamental truth about our being in the world. This truth is something that philosophy has tended to ignore, or minimise, in the interest of a more abstract view. He insists we are in the world, not as minds conjoined to mechanical bodies, but as fully incarnated creatures. In his view, perception itself is a bodily activity. We are not separate from the world; we are woven into it. He sees certain painters – Cézanne, obviously – as registering the fact of embodiment in their art. His early essay, Cézanne’s Doubt, is one of the great texts on 20th century painting.

Merleau-Ponty has meant a great deal to me. My own feelings about art as a young man were intensely ‘bodily’. It was marvellous to discover that’s how he thought it should be. The consideration of embodiment has been basic to almost everything I’ve done in art criticism and art history until now.

Specifically, the issue of embodiment plays a key role in my Caravaggio book. Because of the brilliance of the realism in his paintings, they have tended to be seen in ‘optical’ terms – as if depiction in his art is equivalent to what one might see in a mirror. I’m not claiming this is wholly wrong, but that manifestly at work there’s a relation to his own embodiment and activity in making the paintings – and that we, as viewers, relate to them in a similar way.

Your next choice, Disowning Knowledge in Seven Plays by Shakespeare, is written by a friend of yours, Stanley Cavell.

Cavell is an American philosopher in his mid-eighties who taught for many years at Harvard. We met in 1962 and became close friends when he began teaching there a year later. I’m not alone in finding his books and essays the most profound and helpful works we have on Wittgenstein, arguably the deepest philosopher of the 20th century. My own work has a close connection to both thinkers.

I could have selected Cavell’s philosophical masterpiece, The Claim of Reason, but I chose the Shakespeare book because it has a bearing on my thinking in The Moment of Caravaggio. Shakespeare and Caravaggio were almost exact contemporaries. The great tragedies date from the 1590s and early 1600s, and Caravaggio’s art comes from this period. He died in 1610.

Different as the two men and their cultures were, it makes perfect sense to think of them as contemporaries. Their respective visions are, in a certain sense, complementary, because certain philosophical issues are at stake in their bodies of work. The most important is scepticism. Cavell’s key insight into Shakespearean tragedy is that it expresses the prevalence of a sceptical worldview – we cannot truly know what’s in someone else’s mind. This, Cavell suggests, is why Othello falls prey so easily to Iago. Othello is startled by the sexual feelings he has awakened in Desdemona and is appalled not to know everything she’s thinking.