"Telling us to obey instinct is like telling us to obey 'people.' People say different things: so do instincts. Our instincts are at war... Each instinct, if you listen to it, will claim to be gratified at the expense of the rest"

C. S. Lewis draws a provocative parallel between instincts and people, emphasizing the internal complexity faced when relying on instinct as a moral guide. Instinct is often hailed as a pure, natural source of direction, something untainted and trustworthy. However, Lewis challenges this notion by observing that instincts, much like people, are not monolithic or harmonious. People do not present a single, unified command; they contradict, clash, and call us in various directions. Similarly, instincts can tug a person toward kindness one moment, anger the next, generosity now, self-preservation later.

By claiming that instincts "are at war", Lewis points out the tension and competition inherent within the human psyche. Each instinct speaks forcefully, advocating for its particular gratification, regardless of other impulses or consequences. The voice of hunger disregards the claims of compassion, the urge for revenge ignores the call for forgiveness. If one were to obey every instinct without question, chaos and conflict would ensue internally and externally; not all instincts can be satisfied at once, for they often drive us toward mutually exclusive actions.

Lewis’s observation undermines the idea that morality is as simple as following what is “natural” within us. The diverse and often competing instincts must be weighed, prioritized, and sometimes denied. There is an implicit argument here that a rational or moral faculty distinct from mere instinct is necessary to arbitrate between impulses, to choose rightly when desires come into conflict. Human flourishing, then, cannot rest on blind obedience to instinct. Instead, it depends on discernment, on evaluating which impulses serve the greater good, align with reason, or fulfill a higher standard. Lewis’s insight cautions against naive trust in the arbitrariness of inner feeling: true moral insight recognizes the multiplicity, and sometimes hostility, of our instincts, and seeks a wise reconciliation among them.