Chapter 10 explores epistemological and methodological implications of ECT. The overarching issue is whether one adopts a reductive logic or an emergent logic, and whether one is mainly concerned with linear causation versus emergence. The former helps map out developmental diversity from a population perspective, and the latter inductively derives the emergence of new structures, properties, and patterns through real-time person–task interaction. The further issue is making decisions on using person-centered versus variable-centered approaches. At a more epistemological level, ECT does not endorse the deductive logic of falsification, which has a deterministic connotation. Given the indeterminacy involved in talent development, ECT argues that theoretical predictions regarding short-term and long-term outcomes can be based on soft constraint satisfaction as a new epistemology guiding predictions, which dictates that talent trajectories, pathways, and achievement patterns are indeterminate but principled. The chapter thereby proposes five terms (emergence, adaptation, divergence, excellence, and coherence) as organizing research that taps into probabilistic epigenesis, proximal processes, and developmental self-organization toward higher-order coherence. Each term constrains the structure of inquiry and methodology, including what timescale of action is appropriate, and whether quantitative or qualitative, deductive or inductive methods should be used.