What is present habit was former custom to which no kind or degree of stigma attached.

Bach did it; Handel did it; nor was either of these worthies always scrupulous in distinguishing between meum and tuum when it came to appropriating existing thematic material.

In their day the merit of individuality and the right of property lay more in the manner in which ideas were presented than in the ideas themselves.
In 1886 I spent a delightful day with Dr.Chrysander at his home in Bergedorf, near Hamburg, and he told me the story of how on one occasion, when Keiser was incapacitated by the vice to which he was habitually prone, Handel, who sat in his orchestra, was asked by him to write the necessary opera.

Handel complied, and his success was too great to leave Keiser's mind in peace.

So he reset the book.