Nature versus nurture has shaped centuries of debate—but what if the answer is neither, and both?

In Human Agency: 75% DNA, 25% Free Will, scientist and biotechnologist Muren Herrid, PhD, revisits the classic question of whether our lives are determined by genetics (nature) or environment and experience (nurture)—and argues that modern science demands a more nuanced answer.

Drawing on research in genetics, epigenetics, evolution, and biotechnology, this book examines how DNA powerfully shapes intelligence, behaviour, and physical traits, while also showing how environment, experience, and mental state can influence how genes are expressed—sometimes across generations.

Blending rigorous science with real-world examples and personal reflections, Human Agency explores:

Why genetics explains more about human differences than we often admit How epigenetics blurs the line between nature and nurture Whether mental state and conscious behaviour can influence biology What evolution looks like in the age of AI, gene editing, and Neuralink How humanity may actively participate in its own future evolution Written for curious readers, science enthusiasts, policymakers, and professionals, this book challenges simplistic answers to the nature-versus-nurture debate and replaces them with a biologically grounded, evidence-based framework.

If you’ve ever asked whether your destiny is written in your DNA—or whether free will still matters—Human Agency offers a compelling scientific perspective on who we are, and how much choice we truly have.