When the art historian Gustav Waagen saw Diogenes in the collection the 2nd Earl Grosvenor he mistakenly attributed it to the Spanish Jusepe de Ribera. It was not until Mantovanelli noted its similarity to Giovanni Battista Langetti's altar wings of Saints Peter and Paul in the Domenican church of San Daniele, Padua, that it was given to the Genoese painter (Mantovanelli, 1990, loc. cit.).

Although Langetti moved to Rome at an early age to study under Pietro da Cortona, he was most influenced by the art he encountered later in Naples, probably in the mid-1650s. There, he studied the work of Ribera, Francesco Fracanzano, and Luca Giordano, all of whom influenced his dramatic compositions, vigorous brushwork, and strong chiaroscuro.

The altarpiece Langetti painted for San Daniele, Padua, (and by extension we can presume the present work), was painted in 1675-6, in the last year of his life. The similarities between these works are profound, particularly in the construction of the oversized cloaks and in the impressive modelling of the uncovered arms of both Saint Paul and Diogenes. In the present picture Diogenes is depicted by Langetti leaning on a closed book, isolated in his solitude; behind him the artist has painted a large barrel, in which the philosopher reputedly slept.