This paper uncovers the scientific foundation of traditional systems of Indian medicine: Siddha and Ayurveda, from core principles shared in modern control systems engineering. Grand challenges of modern healthcare are motivating a paradigm shift towards systems of systems (SoS) approaches. The recent emergence of modern systems biology and the concomitant growth of evidence-based research in ancient systems of holistic medicine such as Siddha and Ayurveda, practiced in India for over 5,000 years, exemplify this shift. This paper reveals a Rosetta Stone, inscribed from principles of control systems engineering, to comprehend the scientific foundations of the ancient lingua franca of Siddha and Ayurveda. This discovery provides a much-needed integrative framework, across east and west, ancient and modern, to develop a systems medicine that overcomes the reductionism of modern healthcare.Keywords: traditional medicine; siddha; ayurveda; complementary and alternative medicine; CAM; systems biology; systems theory; whole cell modelling; Dosha; Prakriti; multi-scale modelling; healthcare system; control systems engineering; systems of systems engineering; SoSE. After attending NYU, in 1978, as a 14-year-old, he was recruited as a research scholar by the University of Medicine and Dentistry of New Jersey, where he invented email, the first full-scale electronic emulation of the interoffice mail system (inbox, outbox, memo, etc.)