Clinical semiology — the art and science of gathering and interpreting clinical signs and symptoms — has been practised since antiquity, yet its role in modern medicine is increasingly questioned in the era of sophisticated imaging, laboratory analytics, and artificial intelligence (AI). In this review, we present evidence that history taking and physical examination remain the cornerstone of the diagnostic process, accounting for approximately 76–82% of diagnoses in primary and secondary care settings. We examine the diagnostic accuracy and likelihood ratios of key clinical signs across major organ systems, discuss the consequences of declining bedside skills on diagnostic error rates, and explore how contemporary tools — including point-of-care ultrasonography (POCUS) and AI-assisted decision support — should complement rather than supplant semiological competence. We further highlight the pivotal and expanding role of internists, who, at the interface of primary and specialized care, are uniquely positioned to preserve, integrate, and advance clinical semiology in complex diagnostic reasoning. We conclude that semiology is irreplaceable, both as a diagnostic technology and as the foundation of the therapeutic physician–patient relationship, and propose a framework for its renaissance in 21st-century medical education and practice.