His variable humour and caustic tongue made him at once a terror and an attraction in whatever society he moved, and it is evident from the tone of Goethe's reminiscences of him that his intercourse with Merck was a mixed pleasure.

But, as we have seen, it was an abiding principle of Goethe to be repelled by no one who had something to give him, and Merck possessed qualities and accomplishments which were of the first importance to him in the phase through which he was now passing.

Merck was keenly interested in literature, especially in English literature, and had all Goethe's enthusiasm for Shakespeare.

Though his own original productions were of mediocre quality, he had an insight into the character and genius of others which Goethe fully recognised and to which he acknowledges his special obligation.

His general attitude in criticism was "negative and destructive," but this attitude was entirely wholesome for Goethe at a period when instinct and passion tended to overbear his judgment.