In a letter to the editor published in the adjacent column, Lee Rosenbaum, one of the opponents of New York Public Library’s sale of the painting “Kindred Spirits,” insists that she is not asking legislators to prevent free trade in art. Yet she concludes by calling “urgently” for “legislation” to “prevent cultural institutions from yielding to the growing temptation to turn a quick profit by selling what they are meant to preserve.” If that’s not preventing free trade in art, it’s hard to see what is.

Ms. Rosenbaum writes that, “strapped for cash, the library suddenly decided that it no longer needed to keep in the public domain masterpieces that it had proudly displayed for generations.” She accuses the library of wanting to turn a “quick profit.” Yet there was nothing “sudden” or “quick” about the New York Public Library’s decision to sell some paintings; it was the product of a deliberative process that stretched over more than two years.

Lee Rosenbaum has views about how the library should prioritize its fundraising and its allocation of its resources; she openly calls for the legislature and the attorney general to enforce those views. For our part, as we pointed out in our editorial on the matter of “Kindred Spirits,” it’s hard for us to see how the legislature or the attorney general or Ms. Rosenbaum would be a better steward of the library’s interests than the library’s own trustees, who have made the institution a national treasure and who know a lot more about running a library than does Eliot Spitzer or the politicians in Albany.

We recognize there’s a lot of sentiment around town to the effect that if the library wanted to sell “Kindred Spirits,” the sale should have been handled in a way that would have given the upper hand to the Metropolitan Museum of Art. It was difficult for the Met to get the painting in a system of sealed bidding, the argument goes, because if it bid too high, it would have, as a public institution, kicked up a controversy. We have also heard the argument that since the library gets some public money, it has an obligation to the city. But that is recognized by the city’s participation at the trustee level, where the sale went through.

The fact is that New York City is blessed with a healthy competitive market in libraries. The Queens Library is a separate institution entirely from the New York Public Library, as is the Brooklyn Public Library. Library patrons or donors of money or books or art or manuscripts may choose to give or frequent those institutions, or the New-York Historical Society or the New York Society Library or the Morgan Library or one of the many New York-based colleges that have libraries. Last month was the New York Public Library’s Lions dinner and the Brooklyn Public Library Foundation’s annual gala. Donors can choose freely among them.

Ms. Rosenbaum says the restrictions imposed on the Metropolitan Museum of Art in the 1970s protect the public patrimony. But the Metropolitan Museum is an art museum, which is a different animal from a library. The restrictions on the Metropolitan Museum, introduced in 1973, require that any works of art worth more than $50,000 must be sold by public auction and the proceeds can only be used for further acquisition of art and not for maintenance or any other purpose. But as the library’s recent sales show, sometimes a sealed-bid auction is better at generating funds than a public auction.

We’d argue that the Metropolitan’s trustees, and the library’s, along with both institutions’ professional staffs, make better judges of the art market than do New York state bureaucrats. It’s the trustees who are best equipped to judge whether a sale will deter future gifts or fund needed acquisitions. If a donor or his estate wants to sue to enforce a gift agreement, or publicly to protest the abrogation of such an agreement, that is one thing. But in the absence of such an agreement or such a protest, we’ll take the judgment of the trustees over that of Ms. Rosenbaum or Mr. Spitzer.