Our Little Life Is Rounded with Possibility - Issue 111: Spotlight

In this special issue we are reprinting our top stories of the past year. This article first appeared online in our "Hidden Truths" issue in June, 2021. If you could soar high in the sky, as red kites often do in search of prey, and look down at the domain of all things known and yet to be known, you would see something very curious: a vast class of things that science has so far almost entirely neglected. These things are central to our understanding of physical reality, both at the everyday level and at the level of the most fundamental phenomena in physics--yet they have traditionally been regarded as impossible to incorporate into fundamental scientific explanations. They are facts not about what is--"the actual"--but about what could or could not be. In order to distinguish them from the actual, they are called counterfactuals. Suppose that some future space mission visited a remote planet in another solar system, and that they left a stainless-steel box there, containing among other things the critical edition of, say, William Blake's poems.