Never before illustrated in any publication, this picture belongs to the famous series of philosophers painted by Giambattista Tiepolo and his sons, and for which the key document is Giandomenico Tiepolo's series of etchings, executed in 1757-8 and published in two volumes as the Raccolta di Teste numero trenta dipinte Dal Sig.r Gio: Batta Tiepolo, Pittore Veneto...Incise da Gio. Domenico suo Figlio. As Professor George Knox has shown (op. cit.; see also G. Knox, '''Philospher Portraits'' by Giambattista, Domenico and Lorenzo Tiepolo', in The Burlington Magazine, CXVII, March 1975, pp. 147-55, figs. 31-46), in a large number of cases the prints can be linked to specific drawn and painted prototypes by Giambattista, including chalk drawings (Knox, 1970, Teste I.2, 22), pen and wash drawings (Teste I.10, 30) and details of large paintings (Teste I.12, 20, 21). There seems to be no reason to doubt Giandomenico's claim in the title of the Raccolta that all of his prints for its two volumes were based on original designs by Giambattista. This leads Knox to affirm the existence of some twenty easel paintings of such heads by Giambattista, not all of which have been traced. Although the Raccolta was not published until circa 1770-4, documentary evidence, including letters between Zanetti and Mariette, arguably the greatest connoisseurs and collectors of prints and drawings in the eighteenth century (see Knox, 1975, pp. 151-2), leaves little doubt that the etchings were in preparation some 12 to 15 years earlier. One must assume that Giambattista's painted prototypes were either painted before circa 1757, or in preparation at the same time as Giandomenico was producing the etchings after them. It is easy to imagine the collaborative project as one of intense interest to the Tiepolos, set against the busy activity of their tightly-knit family studio. In his 1975 article Knox made the first steps towards providing a framework for the distinction of Giambattista's painted prototypes from emulations produced by his sons, which, as in this case, can be of exceptional quality.
Knox (1970, loc. cit.), lists six other versions of the present type, of varying quality, of which the most widely-known is that in the Rusconi collection, Trieste (published as 'Attributed to Giambattista Tiepolo' in M. Gemin and F. Pedrocco, Giambattista Tiepolo: I dipinti, Opera completa, Venice, 1993, p. 511, no. 54). Like the Rusconi version, the present picture is in reverse to the print, indicating its extreme proximity to the unidentified prototype by Giambattista. It is distinguished by its sensitive depiction of the features of the model, showing a touching and nuanced understanding of old age. The long, translucent shadows cast over his eyes and cheekbones draw a psychological distance between the viewer and the depicted; one can tell that he is lost in profound meditation, but nothing about his calm demeanour gives away his thoughts. The bright, vibrant colours of his hat and mantle, the glinting highlights on the antique cameo that crowns his forehead, the luxurious tangle of brushstrokes forming the fur around his neck, the energetic, vigorous handling of the paint in his facial features - typical of the Venetian brush - all these effects are ultimately overpowered by the deep quietude, solidity and calm expressed by the delicately observed face of this philosopher. Beneath the long, white hairs of his mustache, Giandomenico has taken care to show his lips, slightly parted as though about to take the deep, quiet breath of a confirmed stoic.