Page:Hofstede de Groot catalogue raisonné, Volume 1, 1908.djvu/11

 PREFACE THE advantages of a critical and descriptive catalogue of works of art need no discussion. It is generally agreed by experts that one cannot pass judgment on the work of an artist unless one knows his productions, and that one's judgment will gain in precision with the extent of one's knowledge. 1 Those paintings which have not found a permanent home in public collections tend more and more to be scattered over the wide world. For the individual student it becomes, therefore, a task of increasing difficulty to gain a complete knowledge of these works from personal inspection. Not only are pictures banished to California, South Africa, or Australia ; they may also at a public sale pass through an intermediary into the hands of a recluse, so that for a generation or longer they may be hidden from the view of the amateur of art. The only method of preserving these vagrant pictures for the benefit of students is to reproduce them, or, as reproduction is in most cases impossible, to describe them. The English picture -dealer John Smith was the first to recognise this fact, or, rather, to carry out the idea in a practical way. Between 1829 and 1837 he published eight volumes of " A Catalogue Raisonne of the Works of the most eminent Dutch, Flemish, and French Painters ; in which is included a short biographical notice of the artists, with a copious descrip- 1 Only practising artists still sometimes believe that, merely because they are themselves artists, they are qualified to pronounce a decisive opinion on old works of art, without possessing any real knowledge of what the supposed painters of those works accomplished. V