Kant and the Ethical Duty Not to Lie

null, James Mahon (Lehman College, Lehman College)

The Stapledon Colloquium Series features academics from the UK and beyond presenting current philosophical research. The seminars are free and open to members of the public. The seminar takes place on Thursdays, 3-5pm at the School of the Arts Library, 19 Abercromby Square, Liverpool L7 7BD.

Kant’s Groundwork of the Metaphysics of Morals (1785) appears to claim that we have a perfect ethical duty to others not to lie and provides as an example of a lie a false promise to repay a loan – possibly the most famous example in all ofhis moral philosophy. However, according to Kant’s The Metaphysics of Morals(1797) and On a Supposed Right to Lie from Love of Humanity (1797), we have no such ethical duty to others not to lie. According to these later works, we have a perfect ethical duty to ourselves not to lie, and the worst lie we can tell is the lie to oneself, despite the fact that “it seems more difficult to explain how they [lies to oneself] are possible… [because] to deceive oneself on purpose seems to contain a contradiction” (The Metaphysics of Morals, 6: 430). In this talk I try to solve the puzzle of what Kant says about lying in the Groundwork and explain the true ethical duty not to lie in Kant’s moral philosophy.