The story of the cynic philosoper Diogenes was a favourite source of subject matter for Rosa. He painted three versions of Diogenes throwing away his Cup, (Statens Museum, Copenhagen; Palazzo Pitti, Florence; and private collection, New York), and, in around 1645, the large Alexander and Diogenes in the collection of the Earl Spencer at Althorp. Whilst in all these works Rosa set the narratives against a landscape background, in this newly discovered picture, Diogenes is depicted half-length, holding his lamp and book, according to a format first employed by the artist in a number of 'Riberesque' depictions of Saints and Philosophers that featured prominently in his early output. Moreover, the pose of the subject, standing in three-quarter profile, looking over his shoulder as if into a mirror, is conventional for an artist's self-portrait and consistent with Rosa's own self-portraits from the 1640s (see for instance the Self Portrait as an Artist in the Uffizi, or the Self Portrait as Pasciarello sold in these Rooms, 15 April 1992, lot 45). Whilst, given his sympathetic understanding of the philosophy of Diogenes, Rosa might have wanted viewers to see himself in the guise of a modern cynic, any resemblance between the present facial type and his certain self-portraits is uncompelling. Nevertheless, Baldinucci noted that Rosa often made use of a mirror in his studio to study his own expressions and gestures in order to make pictures from them and it is tempting to assume that the present picture may have evolved in this way. In this respect, this canvas might relate to a small group of tesaccia datable to circa 1650, such as the picture in the collection of Sir Denis Mahon and the (so-called) Diogenes sold in these Rooms, 19 January 1951, lot 53 (see M. Mahoney, The Drawings of Salvator Rosa, II, New York and London, 1977, nos. 31.2A and 31.12A respectively).