When medical combatants agree to engage in a scientific debate, they usually do so because they enjoy a friendly competition or because they feel passionate about their point of view. Although I did not receive a Jesuit education, the opportunity to spar with the “champ” (Dr Gattinoni has certainly earned that title) was too much of a challenge to pass up. As to the passion about my side of the argument, I will not go overboard but want to emphasize that I do practice what I preach. I will build my case on the foundations of lung mechanics and my interpretation of experiments designed to unravel the biophysical determinants of lung injury. I will integrate these with data from observational studies and from lessons I have learned reviewing the ventilator practice in my institution.1 However, the most compelling reason why I endorse “low” tidal volume (Vt) settings for all patients on mechanical ventilation is because I do not perceive harm associated with this practice. The overall objective of the following arguments is, therefore, to contrast the relative risks of ventilating patients with generous Vts (eg, 10-12 mL/kg predicted body weight [PBW]) with those of a low-Vt strategy (eg, 6-8 mL/kg PBW), even when lung function is near normal.