International Skeptics Day is celebrated on October 13th of each year. The staff at National Whatever Day were unable to discover the origin of International Skeptics Day.
Skepticism is generally any questioning attitude towards knowledge, facts, or opinions/beliefs stated as facts, or doubt regarding claims that are taken for granted elsewhere.
Philosophical skepticism is an overall approach that requires all information to be well supported by evidence. Classical philosophical skepticism derives from the ‘Skeptikoi’, a school who “asserted nothing”. Adherents of Pyrrhonism, for instance, suspend judgment in investigations. Skeptics may even doubt the reliability of their own senses. Religious skepticism, on the other hand is “doubt concerning basic religious principles (such as immortality, providence, and revelation)”. Most scientists are empirical skeptics, who admit the possibility of knowledge based on evidence, but hold that new evidence may always overturn these findings.