For those untutored in the scholarship and social science of the art of giving, it may come as a surprise that not everyone is happy about the Buffett-Gates pledge. Some are even downright gloomy.

Bill and Melinda Gates, as you will recall, have joined forces with pal Warren Buffett to ask other billionaires to sign a pledge to give at least one-half of their fortunes to charity. And they have takers. Microsoft co-founder Paul Allen inked the pledge last week. Others are sure to follow. After all, Americans annually give over $300 billion to charity.

That’s pretty good news, right? Wrong.

Just ask Pablo Eisenberg, senior fellow at the Georgetown Public Policy Institute. According to professor Eisenberg in a recent Chronicle of Philanthropy opinion article:

[T]he most troubling issues posed by the Gates-Buffett crusade is its potential to intensify the inequalities that exist both in the nonprofit world and in the rest of society.

Foundations, corporations, and other forms of institutional philanthropy tend to favor the nation’s most-privileged citizens and neglect the neediest people and organizations. An outsize share of the money from those institutions goes to established colleges [including Georgetown University, presumably], hospitals, and arts and cultural organizations. Only a small amount finds its way to organizations that serve vulnerable children, low-income people, minorities, women, the disabled, and other disadvantaged communities.

While colleges, hospitals, and arts and cultural organizations may receive a large share of foundation grants, most of these institutions are congenitally committed to serving the very communities that professor Eisenberg champions.

Where are the hospitals in America where children, the needy, women, and the underprivileged are denied treatment? Where are the arts organizations that shut out minorities, the disabled, and other disadvantaged constituencies? Where are the colleges and universities in 2010 that are not committed to a diversity regime? Where has professor Eisenberg spent the last fifty years?

You would be hard-pressed to find an institution of any scale, for better or for worse, more committed to the nation’s disenfranchised and the canons of racial diversity than institutional philanthropy and the organizations it supports. The Philanthropic Collaborative recently found, for example, that more than “two out of every three dollars of all health grants made by foundations benefit low-income and minority communities.” Contrary to professor Eisenberg’s sentiments, private philanthropy is one area of American society that, without heavy-handed government mandates directing giving, can make a reasonable claim to being colorblind.

I suppose it would come as news to Mr. and Mrs. Gates, whose money has largely gone toward heath care and the education of the dispossessed, that their foundation is perpetuating inequality. This is not to say that institutional philanthropy is without fault or that absorbing billions of new dollars does not present a unique set of challenges. Institutionalizing discrimination against what professor Eisenberg might call vulnerable communities is not, however, one of them.