Paradigm shift in medicine and in clinical reasoning method: time has come for a new chest semiotics.

introductionClinical reasoning in medicine is a complex cognitive process that integrates sensory perception, interpretation, and abductive inference to develop diagnostic hypotheses. Despite the rise of artificial intelligence, the patient-clinician encounter remains rooted in semiotics and a probabilistic approach driven by Bayesian updating. In this context, medical knowledge is viewed as context-dependent and subject to continuous revision based on new clinical signs. MAIN BODY: This paper identifies bedside ultrasonography as a transformative "epistemic mediator" that enhances traditional semiotics by uncovering subtle clinical signs often missed by conventional inspection, palpation, percussion, and auscultation. In managing respiratory diseases, ultrasound provides direct, contextualized data that refines the interpretation of findings such as dullness, altered fremitus, and crackles by linking them to specific anatomical correlates. Based on these principles, the AdET-CHEPHEUS initiative proposes a new paradigm for chest physical examination centered on three pillars: 1) Visual inspection; 2) Auscultation integrated with ultrasound; 3) Palpatory ultrasound evaluation Conclusion: By replacing traditional percussion with more informative and reproducible ultrasound-based methods, this model aligns modern technology with classical clinical epistemology. The integration of ultrasound into bedside reasoning represents a vital evolution in chest semiotics, preserving the human element of the diagnostic process while increasing accuracy.