The Delta Problem: Why Science Communication Needs Premise Archaeology

Science communication theory typically assumes that audiences begin from a state of ignorance— that the communicator's task is to translate expert knowledge for recipients who lack it. Thispaper identifies a hidden assumption in this framing: audiences rarely start from zero. Theypossess vulgar versions of scientific concepts — diluted formulations that retain expertvocabulary while having lost the foundational premises that give that vocabulary meaning. Thispaper introduces the concept of delta (Delta): the set of premises present in expert discourse butabsent from its vulgar counterpart. Drawing on converging evidence from conceptual changetheory, the cognitive science of knowledge illusion, and the sociology of scientific knowledge, thepaper argues that Delta creates learning barriers worse than simple ignorance. When learnersalready possess a vulgar version, acquiring the expert version requires not only learning newcontent but first denying the existing formulation — a high-cost cognitive operation that ignorantlearners need not perform. The paper develops a taxonomy of lost premises (formal,measurement, mechanistic, scope, and relational), proposes premise archaeology as asystematic method for identifying and restoring Delta, and argues for a shift from the translationmodel of science communication to a completion model. A case study of the concept "structure"demonstrates how set-theoretic premises lost in migration from mathematics to managementconsulting explain the practical failures of the popular MECE framework. The paper concludesby analyzing why Delta research remains underdeveloped — it falls between disciplinaryboundaries and serves no existing incentive structure — and proposes institutional conditions forits advancement.