Allport treated social categorization as normal and inevitable, not aberrant

Evidence

Although ingroup–outgroup distinctions had been previously recognized as a source of bias (Sumner, 1906), Allport focused on the normality and inevitability of categorizing social groups. — , Rudman, Laurie A - On the Nature of…, 107

Categorization

• corroborated: 2 independent passages support this claim — , Rudman, Laurie A - On the Nature of…, 107