Insights and puzzles in particle physics

Abstract

I briefly review the conceptual developments that led to the Standard Model and discuss some of its remarkable qualitative features. On the way, I draw attention to several puzzling aspects that are beyond the reach of our present understanding of the basic laws of physics.

Comments: Contribution to 'Fifty Years of Quarks', H. Fritzsch and M. Gell-Mann, eds. (World Scientific, Singapore)