Voinea, Porsdam Mann and Earp’s article, ‘Digital Twins or AI SIMs?’, clarifies the terminology surrounding generative artificial intelligence (AI) systems that imitate individuals, proposing the concept of AI Simulation of an Individual Mind (AI SIM) to provide conceptual and ethical clarity. Building on this contribution, this commentary frames digital representations of individuals along a dynamic spectrum—from imitation, simulation, emulation to replication—that captures increasing technological sophistication and ethical complexity. Rather than offering a static taxonomy, this spectrum emphasises contextual nuance and adaptive, human-centric data and AI governance. While AI SIMs describe what these systems are, a spectrum-oriented approach helps illuminate what they may become and how they should be governed.
Fenwick et al. (2026) studied this question.