Essay on philosophical theories and experimental results on time. The author moves from the section of the International Office of Weights and Measures in Paris, where the Coordinated Universal Time is fixed, to research departments in universities around the world, where he experiments, for example, on the minimum fraction of time we can perceive, or what subjective duration time has. There are works by doctors, psychologists, neurologists. On the other hand, he mentions philosophical theories from classical Greece and Augustine to contemporary philosophy.
In a pleasant way he mixes personal anecdotes and family experiences that make the reading flow. Near the end of the book, he mentions works by Matthew Matell, a neuroscientist, who denies the existence of free will.