[Essay IV xi 6-8] It is from successive compounding of these simple ideas...

[Essay IV xi 6-8] It is from successive compounding of these simple ideas, Locke supposed, that we frame the complex ideas of human passions of every sort-love, hate, desire, joy, sorrow, hope, fear, despair, anger, and envy are all modes of pleasure and pain, considered together with notions about the specific circumstances of their origin. [Essay II xx] On this account of human motivation, the practical efficacy of our morality of good and evil depends upon their perception as pleasure or pain.

If it is to have any genuine motive force, moral value, like natural benefit, must ultimately be defined in terms of pleasure and pain.

["Of Ethics in General" 7-8] Good and evil generally are to be considered nothing more than tendencies to produce pleasure and pain, Locke held, and moral good and evil are nothing other than special instances of this association, the reward and punishment artificially annexed by a powerful legislator as the consequences that follow from human actions by virtue of their conformity with or difference from the dictates of moral law.

[Essay II xviii 5] The central problem for Locke's hedonism is the human tendency toward a myopic appreciation of our own welfare. Since only present uneasiness can determine the will, the future moral consequences of our actions motivate us only through our present contemplation of the pleasure or pain that they will produce. All too often, our delight in an immediate pleasure or our satisfaction with the removal of an immediate pain override the motive force of remote future consequences.

[Essay II xxi 59-64] Pursuit of Happiness The effort to deal with this problem was central to the second-edition account of human volition. Locke withdrew his earlier claim that "the greater Good is that alone which determines the will" in favor of the view that the uneasiness of desire is the proximate cause of every volition, and this requires some careful explanation.

[Essay II xxi 42] For readers who might well have preferred the high ground of the earlier doctrine, Locke emphasized that contemplation of an absent future good can still have motive force, but insisted that it can do so only through the mediation of the present uneasiness it induces in us.