I'm reading, and greatly enjoying, James Knowlson's biography of Beckett : "Damned to Fame".
Knowlson can really use the most cunning analogies to illustrate his man:

On Beckett's unadmitted influence by great classic writers he says " A man who consumes large quantities of garlic does not always realise how his breath, even the pores of his skin , emit its powerful odour".
And on the influence of classic painting Knowlson says " If we could take X-rays of some of Beckett's later plays, we would surely be able to detect some of the ghostly images of the old masters lurking beneath the surface"