Libertarianism, positive obligations and property abandonment: children's rights

The purpose of the present paper is to test this premise of no positive obligations against a challenging critique that can be made of it. To wit, abandonment of babies. That is, does the mother who abandons her baby have the positive obligation to at least place it “on the church steps”, e.g. notify all other potential care givers of the fact that unless one of them comes forward with an offer to take in the infant, it will die? If so, then there is at least one positive obligation in the libertarian philosophy; if not, then, at least at the outset, the libertarian claim to be generally utilitarian must be greatly attenuated. At best, there would now be an exception to the previously impermeable principle of no positive obligations; at worst, one exception tends to leads another, posing the risk that the premise will be fatally compromised, which can undermine the entire philosophical edifice.