Step 1: Concept Identification: The query seeks the individual associated with fundamental Public Relations ethical tenets, specifically "Tell the truth."
Step 2: Detailed Analysis:
(1) Jean Piaget and (2) Lev Vygotsky: Renowned developmental psychologists focused on child cognitive development theories, not public relations.
(4) Sigmund Freud: Founder of psychoanalysis. While his nephew, Edward Bernays, is a PR pioneer, Freud himself was not involved in public relations.
(3) Arthur W. Page: Recognized as the "father of corporate public relations." Serving as AT and T's first VP of Public Relations (1927-1947), he codified ethical and effective PR principles, known as the Page Principles. "Tell the truth" is his most recognized principle. "Manage for tomorrow," another of his seven principles, stresses anticipating public reaction and rectifying detrimental practices.
Step 3: Conclusion: Arthur W. Page formulated and advocated the seven core principles of Public Relations management, including "Tell the truth."