Do non-religious adults – despite their explicit disavowal of religious beliefs – have a tacit tendency to view nature as purposefully created by some being? This question was explored in three online studies using a speeded judgment procedure, which assessed disbelievers in two different Western cultures (United States and Finland). Despite strong performance on control trials, across all three studies non-religious individuals displayed a default bias to increasingly judge pictures of natural phenomena as “purposefully made by some being” under processing constraints. Personal beliefs in the supernatural agency of nature (“Gaia beliefs”) consistently predicted this tendency. However, beliefs in nature as purposefully made by some being persisted even when such secular agency beliefs were controlled. These results suggest that the tendency to view nature as designed is rooted in evolved cognitive biases as well as cultural socialization.