The basic constants of physics fall within narrow life-permitting ranges, which is evidence of a designer.

The values of certain fundamental constants and the initial conditions of the universe sit within very narrow windows that allow stars, chemistry, and living things. Two much-discussed examples are the cosmological constant, the quantity tied to dark energy, whose observed value is extraordinarily small compared with naive theoretical expectations, and the strong nuclear force, which can vary only within a few percent before the chemistry that life needs becomes impossible. Honest limits: that the constants lie in narrow ranges is widely accepted, including by scientists who are not believers. What is disputed is the explanation. We treat design as a natural reading, but the multiverse and plain luck are live rivals, and some scientists expect a future, deeper theory to show the constants could not have been otherwise. We avoid inflated odds, such as precise figures like one in ten to some huge power, presented as proof. Those figures are model dependent, and the reasoning here is a probability judgment, not a mathematical proof.