The great problem of legislation is, so to organize the civil government of a community… that in the operation of human institutions upon social action, self-love and social may be made the same.

Adams frames legislation as an exercise in institutional design rather than mere rulemaking. The “great problem” is to structure government so that ordinary human motives—especially self-interest (“self-love”)—are redirected toward outcomes that also serve the public good (“social”). In other words, good laws and constitutions should align private incentives with civic virtue, so that people pursuing their own advantage are, through the system’s checks, balances, and rewards, also advancing communal welfare. The remark reflects a classical-republican and Enlightenment-inflected view of politics: institutions must take human nature as it is and harness it, not assume citizens will consistently act from disinterested virtue.