For 10 points, identify this movement of not believing in deities.
The medieval Sejm executed Kazimierz Lyszczynski for espousing this philosophical stance. It was championed by the materialist Baron d'Holbach in his The System of Nature, a book sometimes termed this belief's "Bible." Voltaire's Philosophical Dictionary compares this stance to idolatry. The modern day movement Out Campaign supports this stance. Percy Shelley was expelled from the University of Oxford for writing a tract about its necessity. In a book about how a certain figure "is not great," Christopher Hitchens advocates a "new" type of this, which has also been supported by Richard Dawkins. For 10 points, identify this movement of not believing in deities.
The medieval Sejm executed Kazimierz Lyszczynski for espousing this philosophical stance.
atheism