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1.2.6: Perfect and Imperfect Duties

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    89075
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    Recall the example of making a false promise to secure a loan. The maxim is “whenever I can benefit from doing so, I should make a false promise”. The question is whether I could conceive or will that this become a universal law.

    I could not. If everyone followed this maxim then we would all believe everyone else could make a false promise if it would benefit them to do so. Kant thinks such a situation is not conceivable because the very idea of making a promise relies on trust. But if “whenever it is of benefit to you, you can make false promises” was to become a universal law then there would be no trust and hence no promising. So by simply thinking about the idea of promising and lying we see the maxim will fail the test and, because we cannot universalize the maxim, then making a false promise becomes morally impermissible. This is true universally for all people in all circumstances for anyone can, in principle, go through the same line of reasoning.

    A maxim failing at (i) is what Kant calls a contradiction in conception, and failing at (i) means we are dealing with what Kant calls a perfect duty. In our example we have shown we have a perfect duty not to make false promises.

    Consider another example. Imagine that someone in need asks us for money but we decide not to help them. In this case our maxim is “whenever someone is in need and asks for money do not give them money”. Does this pass the CI-1 test?

    No it fails the CI-1 test. Although it is true that the maxim passes (i) not giving to the needy does not threaten the very idea of giving money away. Kant thinks that anyone thinking about this will see that that maxim will fail at (ii) and hence it is morally impermissible. Here is why.

    You cannot know if you will be in need in the future and presumably you would want to be helped if you were in need. In which case you are being inconsistent if you willed that “people should not help those in need” should become a universal law. For you might want people to help those in need in the future, namely, you.

    So we cannot will the maxim “whenever someone is in need do not help them” to become a universal moral law. Again this is a thought process that anyone can go through and it means that this moral claim is true universally for all people in all circumstances. Failing at (ii) is what Kant calls a contradiction in will, and failing at (ii) means we are dealing with what Kant calls an imperfect duty.

    It is absolutely key to recognize that CI-1 is not simply asking “what if everyone did that?” CI-1 is not a form of Utilitarianism (see Chapter 1.1). Kant is not saying that it is wrong to make false promises because if people did then the world would be a horrible place. Rather Kant is asking about whether we can conceive or will the maxim to become a universal law.


    1.2.6: Perfect and Imperfect Duties is shared under a not declared license and was authored, remixed, and/or curated by LibreTexts.

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