In this article, I describe the 21 ideas underlying a 42-year search to understand giftedness. I present the ideas roughly chronologically, in the order in which they arose, and discuss how in a career as in science, progress means supplementing or even superseding one idea with the next. In terms of the 21 ideas, I start with a discussion of how I thought IQ tests could account for giftedness and end with a discussion of the ACCEL (Active Concerned Citizenship and Ethical Leadership) model. But I frame the article in terms of a paradox--that despite the fact that IQs rose 30 points during the 20th century, people often seem to be operating at an intellectual level that is not notably higher and may even be lower in some respects than in previous times.