Muse, Inspiration & Creation

Water Lilies: Is the value of one Monet canvas diminished by the existence of another unique expression of a singular inspiration?  If an artist creates a series of original sculptures, such as did Remington, is the value of one diminished by the existence of the others?  The value of an object d'art that is the product of a true artisan often is enhanced by its place in a series, rather than diminished.