Carl Sagan on Divine command theory

Sagan did not engage with divine command theory as a formal philosophical position, but his broader work makes his rejection clear. He argued throughout his career that human beings are capable of moral reasoning without divine guidance — indeed, that our best moral reasoning occurs precisely when we set aside appeals to authority and think for ourselves.

In The Demon-Haunted World, Sagan drew a connection between scientific thinking and moral thinking. Both require the willingness to follow evidence rather than authority, to change one's mind when the evidence warrants it, and to treat claims sceptically regardless of their source. A morality based on divine command short-circuits this process by replacing evidence and reason with obedience.

Sagan also noted that the history of religion is filled with moral commands we now recognise as atrocious — the endorsement of slavery, the subordination of women, the execution of heretics. If morality came from divine command, these commands were once moral and are now somehow not. The simpler explanation is that morality comes from human beings, who make mistakes and gradually correct them through reason and empathy.