Thinking with computers, developing construals for a scientific phenomenon, and devising instruments are all activities to which EM is well-adapted. All are also quite different in kind from classical computer programming. This begs the question: How can we view a computer-based EM model, if not as a classical computer program? Because EM admits model-building of a personal, pre-articulate, subjective nature, its justification requires a radical shift in perspective on foundational issues in computing such as is envisaged in the research of Brian Cantwell Smith. The ontological issues raised by EM parallel those raised by developments in computing such as brain-mediated communication, virtual realities and intelligent agents. Their most satisfactory resolution can perhaps be found in William James's philosophic attitude of Radical Empiricism, which relates matters of truth and reality to the authenticity and character of varieties of experience.