Life and death, good and evil; yes and no; black and white; male and female; optimist and pessimist; thesis and antithesis—the enumeration could go on forever. Since the dawn of time, opposites have always held much fascination for humanity—witness, among many others, the Pythagorean “Table of Opposites” (6th century BC) with its ten pairs of contrary qualities (limited/unlimited; odd/even; unity/plurality, etc) and the Chinese Taoist philosophical paradigm, which, since the 4th-3rd century BC, lists every existing reality under the two opposite categories of Yin (?) and Yang (?). Originally these two characters designated the sunny side and the shady side of a valley, before becoming the two cosmic principles whose interaction and alternation preside over the genesis and evolution of the universe and constitute the “Tao” (?). But arguably none better than the Book of Ecclesiastes (written ca 250 BC) in the Bible epitomizes how our perception of life hinges on the duality of opposites: These two last categories of opposites (love/hate; war/peace) take us straight to the heart of the matter since they are the perfect illustration of what friends and foes can be associated with. The human body, as any living organism, survives in an environment in which it is vital to distinguish what may kill it or help it thrive, harm it or benefit it. A continuous cycle between opposites, including life and death, takes place in our body cells. Nature exerts its control through sophisticated regulatory systems like an automobile driver applying, in turn, the accelerator and the brake. What is true of the organism as a whole is true of its parts, and in a very special way of its “motor,” the heart, a point abundantly underlined in this issue of Dialogues in Cardiovascular Medicine...