In the Chapter 3, Mill describes the “sanction” by which individuals are obligated to follow the principle of utility. Because moral philosophers are often called upon to provide a justification for any moral code they propose, Mill explains the reasons for following the principle of utility, describing it as a “moral standard.” Individuals who follow the specific moral laws they learned as a child are often immediately skeptical when a philosopher attempts to propose a general principle that underlies moral actions. For this reason, Mill feels he must provide a description of the sanction, or, the “binding force,” by which individuals are expected to follow utilitarianism.

For Mill, the sanction for any moral code can be divided into two groups: external and internal. External sanctions refer to the sense of obligation one feels towards a moral code in order to appease the members of one’s community or God. Internal sanctions refer to an individual’s conscience, which Mill defines as “a [painful] feeling in our own mind” (141) that arises whenever an individual acts immorally. While some individuals do not have a conscience, Mill argues that the vast majority of individuals obey a moral code due to this “subjective feeling in our own minds” (142).