Transformative learning may involve gentle perspective widening or something more traumatic. This paper explores the impact of a transformative pedagogy in a course that challenges learners to "think like a planet". Among six sources of intellectual anxiety, learners worry about: why Gaia Theory is neglected by their other courses; the removal of humans from "crown of creation" status; Gaia's unfamiliar multibillion-year timescales, comprehending the world system as a whole; the array of weaker and stronger Gaia concepts; and the diversity of viewpoints among classmates. Analysis finds that most learners coped with this exercise although some achieved this by compartmentalization.