In his work "On Certainty," Ludwig Wittgenstein reflects on the nature of belief and knowledge, particularly in relation to sensory perception. He poses a scenario where if a blind person inquires about the presence of their hands, one should not depend solely on sight to validate this claim. Instead, he suggests questioning the reliability of one's own senses, emphasizing the need for a foundational form of certainty in knowledge.

This line of reasoning challenges the conventional perspective of verification through sensory experience. Wittgenstein prompts readers to consider the implications of trusting one sense over another and raises deeper philosophical questions about the nature of knowledge and how we ascertain truth. By highlighting this paradox, he underscores the complexities involved in understanding certainty and belief, suggesting that our assumptions about knowledge require a critical examination.