According to the inscription, the picture was a gift by Rosa to his friend Giovanni Battista Ricciardi (1624–1686). Ricciardi was a man of letters and a reader in moral philosophy at Pisa. The painting is listed in an inventory drawn up after Ricciardi's death as "a philosopher who writes on a skull." Although it was later described as a portrait of Ricciardi, the figure resembles Rosa and it is likely to be a self-portrait. The wreath of cypress is an emblem of mourning, while on the table is a book by the Roman stoic philosopher Seneca (Seneca's name is a pentiment; it was painted out by Rosa). The Greek inscription on the skull reads "Behold, whither, when."

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