Lying raises fundamental questions in ethics, epistemology, and philosophy of language. As a first approximation, lying involves asserting a proposition that one believes to be false, typically with the intention of deceiving. Philosophers have long debated the exact definition of lying and how it differs from other forms of deception. Definitional questions include: Does lying require an intent to deceive? Are all lies falsehoods, or can true statements be lies? Can one lie merely by implicating something false, or by non-verbal means? The ethics of lying is another important area of philosophical analysis. Philosophical work in this field focuses on determining what makes lying wrong, and whether this wrongness admits exceptions. While influential thinkers like St. Augustine and Kant argue for a strict prohibition on lying, others allow for exceptions under the right circumstances. Related issues concern the moral permissibility of other forms of deception, and discussion of lying in applied ethics. Finally, lying also connects to epistemological issues surrounding knowledge, belief, and testimony. The possibility of lying threatens to undercut the status of testimony as a source of knowledge. Consequently, epistemologists explore whether and to what extent insincerity threatens our ability to share knowledge by communicating. |