How did Bernard Williams connect moral reasons to a person’s existing motives?

Bernard Williams argued that for a moral reason to be valid, it must be "internal" rather than "external." He maintained that reasons for action must derive from motives that a person already possesses, such as desires, projects, or commitments.1

In Williams's view, reason alone cannot create new motives; therefore, an "external" reason—one that does not connect to a person's existing subjective motivational set—cannot truly provide a reason for that person to act. By insisting that practical reasons must be anchored in an individual's actual motives, Williams challenged ethical theories that rely on impartial or universal standards, which he believed often ignore the individuality and personal projects that give human life its meaning. This perspective emphasizes that moral judgments are deeply tied to the contingency and complexity of a person's life rather than to abstract, objective structures.1