Doubt, uncertainty, or scepticism regarding any subject of dispute.
The view that absolute truth or ultimate certainty is unattainable, especially regarding knowledge not based on experience or perceivable phenomena.
Doubt, uncertainty, or scepticism regarding the existence of a god or gods.
The view that the existence of God or of all deities is unknown, unknowable, unproven, or unprovable.
A movement in the Lutheran church in the 17th and 18th centuries, calling for a return to practical and devout Christianity.