I: Roots of Cognitive Science: Karl Duncker; 1: Karl Duncker and Cognitive Science; 2: Life as the Problem: Karl Duncker’s Context; 3: Duncker’s Account of Productive Thinking: Exegesis and Application of a Problem-Solving Theory; 4: Duncker’s Analysis of Problem Solving as Microdevelopment 1, 2; II: Abstractive Generalization through Language: The Legacy of Karl Bühler; 5: The Pleasure of Thinking: A Glimpse into Karl Bühler’s Life; 6: Remembering Karl Bühler: Discovering Unanticipated Resemblances with My Distancing-Representational Model; 7: Bühler’s Legacy: Full Circle and Ahead; III: Thinking and Speaking: Development through Thinking, Acting, and Speaking; 8: Arnold Gesell and the Maturation Controversy; 9: Alexander F. Chamberlain: A Life’s Work; 10: The Fate of the Forgotten: Chamberlain’s Work Reconsidered; IV: The Dynamic Whole: Gestalt Ideas and Social Practices; 11: Tamara Dembo’s European Years; 12: Between Scylla and Charybdis: Tamara Dembo and Rehabilitation Psychology; 13: Tamara Dembo’s Socio-Emotional Relationships; V: Dissecting Methodology and Thinking of Development; 14: The Legacy of Adolf Meyer’s Comparative Approach: Worcester Rats and the Strange Birth of the Animal Model; 15: Zing-Yang Kuo: Personal Recollections and Intimations of Developmental Science 1 , 2; 16: Kuo’s Epigenetic Vision for Psychological Sciences: Dynamic Developmental Systems Theory