Major findings uncovered by SMPY -- five cohorts of more than 5,000 intellectually talented participants recruited throughout 1972-1997 and tracked over the past 40 years -- are reviewed. These findings have important implications for understanding the psychological differences and educational needs of students who gravitate toward the humanities versus STEM disciplines. The scope of individual differences within the top 1% of mathematical reasoning ability is huge across both intellectual (mathematical, spatial, and verbal abilities) and nonintellectual attributes (interests and personality); and these differences create contrasting developmental trajectories and organizational climates. They cannot be ignored. A model highlighting the multi-dimensionality and scope of human individuality is provided, because taking into account human differences in psychological orientation facilitates educational practice and talent development. This model also helps to identify untapped pools of talent. Among other revealing findings, there does not appear to be an ability threshold (even within the top 1%); more ability is better for enhancing the likelihood of creative achievement in middle age. True “multi-potentiality,” is very rare. And nonintellectual personal attributes in addition to intra-individual ability strength, play a role in determining the domains within which intellectually talented individuals make their creative advances, but opportunity and hard work are both required as well.