Rev. Dr. Gregory I. Simpson is a theologian, scientist and ordained minister in the Presbyterian Church (USA). At the Center for Earth Ethics, he brings a unique perspective to environmental justice work, informed by his deep experience in faith leadership and STEM education. He has served in various roles with the Center since its inception, including as co-chair of the advisory board. He now continues his work at CEE as a Senior Fellow focusing on the intersection of spirituality and science, with special attention to the impact of rapidly changing technology on environmental justice advocacy, and spirituality and faith practices. 

Rev. Simpson currently serves as pastor of Nauraushaun Presbyterian Church in Pearl River, NY. He is treasurer of the Synod of the Northeast, overseeing financial policy and investment strategy. He also chairs the PCUSA’s Environmental Justice & Climate Change subcommittee. Regionally, he serves as the chair of the Ulster County Economic Development Alliance board, and a trustee of SUNY Ulster Community College. He has served on the boards of Riverkeeper and Hudson River Clearwater, and was a co-founder of the Hudson Valley Environmental Justice Coalition.

Before entering ministry, Rev. Simpson spent over 30 years as a STEM educator and researcher. He holds a Ph.D. in Organic Chemistry, with work published in molecular physiology, analytical chemistry and natural product chemistry. He later earned Master of Divinity and Master of Sacred Theology degrees from Union Theological Seminary, focusing on New Testament studies. He wrote theses on intellectual property rights and eco-justice.

Born in Glasgow, Scotland, Rev. Simpson has received numerous honors for his work in science, faith and justice, including being awarded a Sinai and Synapses Fellowship in 2019, his appointment and election to a full term on the Town Board of Hurley NY in 2022 and 2023, and receiving the MLK Jr. Award for Environmental Justice Advocacy from the Ministers Alliance for Ulster County in 2023. His leadership continues to inspire communities toward spiritual and environmental renewal.