संशयवाद (skepticism) वह मत है कि पूर्ण, असंदिग्ध या विश्वसनीय ज्ञान की प्राप्ति असम्भव है, अथवा किसी क्षेत्र-विशेष में या साधन-विशेष से ऐसा ज्ञान प्राप्त नहीं हो सकता।

Skepticism, also spelled scepticism in British English, is a questioning attitude or doubt toward knowledge claims that are seen as mere belief or dogma. For example, if a person is skeptical about claims made by their government about an ongoing war then the person doubts that these claims are accurate. In such cases, skeptics normally recommend not disbelief but suspension of belief, i.e. maintaining a neutral attitude that neither affirms nor denies the claim. This attitude is often motivated by the impression that the available evidence is insufficient to support the claim. Formally, skepticism is a topic of interest in philosophy, particularly epistemology.