The Court's reasoning in *Brown* was multifaceted, but centered on the idea that:
* Separate is inherently unequal: Even if ostensibly equal in terms of resources and facilities, separate educational facilities are inherently unequal because segregation itself creates a feeling of inferiority that negatively impacts the education and psychological development of African American children. This psychological harm was deemed to be a violation of equal protection. The Court rejected the "separate but equal" doctrine established in *Plessy v. Ferguson* (1896) which had previously allowed for racial segregation in other public facilities.
* State action: The Fourteenth Amendment applies to state action. Public schools are state-funded and operated, making segregation in them a violation of state-mandated action.
Therefore, by creating a system where black children were denied equal educational opportunities solely based on their race, segregated schools were deemed unconstitutional, violating the guarantee of equal protection under the law as enshrined in the Fourteenth Amendment. The tangible inequality (e.g., unequal funding, resources) and intangible inequality (e.g., psychological harm from segregation) were both central to the Court's decision.