Conditionals are a feature of historiography. Despite this, historiographical research is focused predominantly on one kind of conditional, counterfactuals. New trans-Atlantic contributions to this research by Catherine Gallagher and Richard J. Evans highlight the rich history of counterfactuals in Western thought, and their use by individuals and groups to imagine a present and a future that addresses regrets about the present. Their intimation of a flattening out of history through counterfactual nostalgia is not supported by the artistic expression of Tacita Dean, and new contributions to the philosophy of conditionals, building relations, and causal relations by Karen Bennett and Anthony Kwame Appiah. This review teases out the layered, causally tainted, and metaphysically agnostic world posited by Karen Bennett and conjoins it with David Lewis's reflections on possible worlds to suggest that conditional and counterfactual operators in historiography are building restrictors. This takes us away from Niall Ferguson's argument for the use of counterfactuals as a recognition of the underdetermination of history, and reminds us of the need to—as Appiah argues so succinctly—understand the pervasive role that idealizations play in helping us to manage the world and ourselves. The review rounds out by highlighting the computational implications of our conditional world, inviting historians to be at the table as fairness is debated and coded. In this way, the gap in research on the ethical need for historiographical conditionals in the twenty-first century is highlighted.