Joseph Petek is the Director of Research and Publication of the Whitehead Research Project of Gonzaga University and Executive Editor of The Edinburgh Critical Edition of the Complete Works of Alfred North Whitehead. He has co-edited three books on Whitehead: Rethinking Whitehead’s Symbolism (2017), Whitehead at Harvard, 1924–1925 (2020), and The Harvard Lectures of Alfred North Whitehead, 1925–1927: General Metaphysical Problems of Science (2021). His latest book is Unearthing the Unknown Whitehead (2022), which examines the significance of Whitehead's Harvard lectures and other previously unknown archival materials. Brian G. Henning is Professor of Philosophy and of Environmental Studies and Sciences at Gonzaga University and Executive Director of the Whitehead Research Project. Dr. Henning holds a M.A., M.Phil., and Ph.D. in philosophy from Fordham University. He is author or editor of fifteen books and more than thirty-five articles and chapters. His 2005 book, The Ethics of Creativity (University of Pittsburgh Press), won the 2007 Findlay Book Prize from the Metaphysical Society of America for the best work of metaphysics published between 2001 and 2006. He is the Founder and General Editor of The Edinburgh Critical Edition of the Complete Works of Alfred North Whitehead.

• AcknowledgementsAbbreviationsIntroduction: Assessing and Defining Whitehead's Harvard LecturesPart I: The role of biology in Whitehead’s philosophy1. From a Philosophy of Evolution to a Philosophy of OrganismPaul A. Bogaard2. Assessing Whitehead’s ‘biological turn’Philippe Gagnon3. Whitehead and Biology – A reply to Philippe GagnonDennis Sölch4. Further Clarifications Concerning ‘Assessing Whitehead’s “biological turn”’Philippe GagnonPart II: Mathematics, Logic, and Symbolism5. Symbolic cognition of infinity: Using Whitehead’s HL2 to bridge Symbolism and Principia MathematicaLandon D. C. ElkindPart III: Whitehead’s Philosophical Context6. The dipolar character of being in Plato and WhiteheadDaniel A. Dombrowski7. The emergence of organic empiricism in Whitehead’s Harvard lectures: relational stubbornness and the being of practiceChristian Frigerio8. Reason in action: Dewey’s place in Whitehead’s Harvard lectures (1925–27)Maria Regina BrioschiPart IV: Metaphysical Reflections9. Whitehead’s ethics: Fill in the blanksMilan Stürmer and Daniel Bella10. Whitehead on solidarity: From the concrete to the systemAlessia Giacone11. Standing firm in the flux: On Whitehead’s eternal objectsMatthew David Segall12. Whitehead’s 1925–27 view of function and timeRonny DesmetNotes on ContributorsIndex