In his defense of utilitarianism, Mill points out several stated objections to it.  One such objection is that utilitarianism fosters "too high" of a moral standard.  This argument is made by some who believe that the notion of putting "society first" in all moral calculations is too difficult as it reduces the role of self.  Mill asserts this in his writing:

...the happiness which forms the utilitarian standard of what is right in conduct is not the agent's own happiness but that of all concerned. As between his own happiness and that of others, utilitarianism requires him to be as strictly impartial as a disinterested and benevolent spectator. In the Golden Rule of Jesus of Nazareth, we read the complete sprit of the ethics of utility.

The mere invocation of Jesus and the Golden Rule helps to dispell the objection that utilitarianism posits too high of a moral standard by rendering it equal to an establish Christian rule of conduct.

Mill responds to this in a couple of ways.  The first is that Mill suggests a difference between "animal" instincts and "human" instincts.  In the former, individuals are no different than animals, responding to the baser elements of their being.  Mill unabashedly says that humans are not animals, but rather are human beings.  This means that they are capable of more advanced and elevated thought and courses of action.  In this light, Mill suggests that the moral standard of putting others' interests first is not that radical and difficult.  Mill suggests that individuals already do this in "private utility."  

Mill argues that in our private domains and relationships, human beings constantly put others' needs before their own and look out for the greatest happiness for the greatest good.  This private utility is seen in husbands and wives who place the happiness of the other in front of their own, or in fathers and mothers who sacrifice their own happiness for the sake of their children.  In this demonstration of private utility, Mill's point is that individuals already demonstrate the greatest good for the greatest number, thereby demonstrating that it is not too high of a moral standard to achieve.

Mill also makes the argument that since human beings are differentiated from animals, there are intrinsic triggers within the psyche that forge connections with other human beings.  Mill's point here is that individuals feel a great sense of human connection with people they don't even know at times because of their intrinsic nature of empathy or sympathy.  Such benevolence is another example of humans being different than animals, in Mill's argument.  

Since human beings already possess these characteristics, it is feasible to see individuals as able to condition themselves towards an understanding in which "the greatest good for the greatest number" can be achieved.  For Mill, this point serves to repudiate the argument that utilitarianism holds "too high of a moral standard."  Mill believes that it is within human beings to embrace such a standard for we already demonstrate that it is so.