Two Rubens, two views

There's an interesting exhibit at the Hermitage Museum of two versions of a single painting by Pieter Paul Rubens entitled The Statue of Ceres.

One version has been part of the Hermitage collection since 1768. The other version is privately owned by Mr. Herman Bayeler, who resides in Switzerland.

The Hermitage has a short explanation of the exhibit. Here's the most unique section:

When repeating his works, Rubens, as a rule, changed something in them, whether details of secondary importance or separate features in the appearance of the main personages. Researchers believe that the Ceres which now belongs to the Bayeler collection was made approximately in the years 1615 – 1617 and is more likely another version of the Hermitage painting by the artist than a simple duplication.

Interesting, wouldn't you say?