Intrusive IntuitionsAttention to humans’ maturationally natural dispositions of mind concerning contaminants will help to answer this question. When cued, the resulting sensitivities, like all maturationally natural cognitive systems, operate unreflectively, easily, automatically, instantaneously, and mostly unconsciously and inarticulately. Scientific education, however, does not erase maturationally natural cognitive biases. The constellation of maturationally natural systems’ properties described above ensures that, when cued, these systems’ arousal is intrusive. This suggests that vaccine hesitancy will repeatedly tempt people, particularly those unlikely (or unable for whatever reason) to reflect on the biological science informing vaccination.