<p>Digital surrogacy (i.e., the creation of AI-based “clones” that autonomously act in ways consistent with their user’s knowledge, personality, and goals) promises to redefine personal productivity. This paper develops a framework to analyze this emerging phenomenon. First, drawing on cognitive externalism, it conceptualizes surrogates as genuine cognitive extensions, identifying three interlocking ramifications: scaled individuality, which enables identity-faithful replication across multiple contexts; black-box productivity, which delivers unprecedented output while obscuring underlying processes; and autonomy inversion, a trade-off where users relinquish decision-making for cognitive relief. Second, the analysis integrates Self-Determination Theory to argue that the success of digital surrogacy is conditional, creating critical tensions with the basic psychological needs for autonomy, competence, and relatedness. Third, it examines existing legal frameworks such as power of attorney and AI personhood, proposing that surrogates are better understood as legal extensions of the person (“empersonification”), which necessitates novel governance structures. By distinguishing digital surrogacy from related concepts like AI Agents and Digital Twins through its core principle of identity-congruent agency, this paper challenges self-centric productivity models. It concludes that the future of work must account not only for distributed cognition but also for the psychological and legal conditions that make such identity-extended agency sustainable and legitimate.</p>