Over 150 years since Claude Bernard coined the evocative phrase, “milieu intérieur”, to draw attention to a deep mystery in the natural world, fundamental questions remain open about how the simplest living system, a bacterial cell, maintains homeostasis of its best studied attribute, cell size. In this talk I will address how life shapes time in a bacterial cell, and examine the interplay between homeostasis and adaptation in this context. First, I will first establish that stochastic intergenerational bacterial cell homeostasis_is_ maintained under appropriate growth conditions, using our precision measurements. Next, the emergent simplicities revealed by these data. Following this, a fitting-free theoretical framework, consistent with observed scaling laws and phenomenology. This naturally leads to a proposal for the underlying mechanistic model. Finally, the extension to time-varying growth conditions, and new emergent simplicities