Inevitably, given the hostility with which his work was often greeted, Manet was subject to dark moods. His letters to the poet Baudelaire evidence his frequently anguished and doubtful periods.

So it’s not surprising that Manet loved music, as an antidote to the undoubted stresses of his life as an artist. He gave fortnightly musical evenings at one stage, and had a deep love for Haydn. Manet’s wife was a talented pianist, and she was frequently one of the performers.

One of his staunchest supporters, from the earliest days, was Zacharie Astruc, and The Music Lesson is one of Manet’s portraits of Astruc and his wife. Astruc was a polymath – writer, musician, journalist, poet and sculptor.

We know that Astruc composed a Moorish lament for single guitar, and dedicated it to Manet, who provided an illustration for it, so it may well be that the picture is a compliment to the composer. Our understanding of these relationships is further enriched when we look at the famous painting Un atelier aux Batignolles (A Studio at Batignolles) by Henri Fantin-Latour.

Manet and various other Impressionist painters lived in the area of Batignolles. The painting shows Manet sitting before an easel, with a number of painters gathered around him, including Renoir and Monet. Zola and Astruc represent writers associated with these avant-garde artists. All the men look grave and are dressed sombrely – a bid to be taken seriously perhaps. Fantin-Latour exhibited this painting at the Salon in 1870 – the same exhibition at which Manet exhibited The Music Lesson; a sign of how central Astruc was to cultural life at this time.

Astruc organised Manet’s 1865 trip to Spain, and was himself a great lover of the country, so it’s appropriate that Manet has painted him playing a guitar. His wife sits next to him, following the score with her finger, and presumably correcting him, since the painting is called The Music Lesson. However we have no record of whether Astruc’s wife was an accomplished guitarist.

Many art critics claim that when music is shown in a painting, it is always a metaphor for painting, and that a pointing finger (Astruc’s wife) is particularly significant. However, Manet was not a great user of metaphor, and the literal connections with music here, do not appear to favour a metaphorical interpretation.