The quality or state of being atheistical; the characteristic of relating to or being atheistic in nature.
From 'atheistical' + '-ness,' which forms abstract nouns describing qualities. This compound creates a rarely-used term for the abstract concept of atheism's essence.
Early English philosophers struggled to describe the concept of 'atheisticalness' because they had no modern framework—they were trying to label something their society considered almost unthinkable!
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