James Rachels, a philosopher, criticized Ayn Rand's Objectivism as simply a type of Ethical Egoism, or the notion that the self comes before all else. His criticism relies on the idea that the moral stance of Objectivism is rooted in arbitrary ideals, none of which are scientifically or philosophically concrete.

According to Rachels, the best argument against ethical egoism is its unacceptable arbitrariness. The egoist arbitrarily assumes his interests come before those of other people.
(LaFave, "Psychological Egoism and Ethical Egoism," instruct.westvallet.edu)

Rachels, in his book The Elements of Moral Philosophy, outlined some of the attributes of an ethical egoist code:

1. People are responsible for their own actions and well-being, and not responsible for the actions and well-being of others without choice
2. Altruism without choice becomes a norm of slavery to others, without 
3. Self-interest is the base from which most moral standard derive their efficacy and importance
   (Ethical Egoism, Wikipedia)

Essentially, Rachels argues that the choiceinherent in the moral choicecode of Objectivism is too arbitrary to be rationally meaningful. Without a concrete foundation of either philosophy or precedent, Objectivism acts as an excuse to act entirely in self-interest without concern for others, moral or not. He also rejects the idea that charity is inherently immoral because of its devaluing effect on the receiver; Rachels instead claims that forms of Utilitarianism, where the morality of action and choice is based on overall "happiness," is a better moral system.