Duty and Kant
Use Kant's two tests, 'what if everyone did this?' and 'am I using this person?', to judge an action by its principle rather than its payoff, and know where his view gets too rigid.
DUTY FIRST
Why you do it matters
Kant (1724–1804) argued that the only thing good without any qualification is a good will: wanting to do what's right because it is right. Results can go well by luck. What gives an act moral worth is acting from duty, not just acting in line with it.
Kant's own example: a shopkeeper who never overcharges an inexperienced customer, even a child, only because an honest reputation is good for business. He does the right thing, but for his profit. Kant says this deserves no special moral credit; the same act done because cheating is wrong does.
Check yourself
Leila finds a wallet and returns it, but only because she noticed a security camera and feared trouble. On Kant's view, her act has full moral worth, because the right thing happened.
Show the answer
False
False. The owner got the wallet back, which is good, but Leila acted in line with duty, not from it. Her reason was fear of trouble. For Kant, moral worth depends on the principle you act on, not on how things turned out.
The categorical imperative (universal law)
Kant's main test. Put your plan as a personal rule, a maxim: 'When I'm in situation X, I'll do Y to get Z.' Then ask: could I will that everyone follow this rule? If the rule would collapse when everyone used it, or you couldn't honestly want that world, the act is wrong.
Kant's example: borrowing money with a promise you know you won't keep. If everyone made false promises when short of cash, nobody would believe a promise, and the trick would stop working. The maxim defeats itself, so it's wrong.
Two kinds of 'ought'
Hypothetical
'If you want to pass, study.' It binds you only if you want the goal. Don't care about passing? The ought disappears.
Categorical
'Don't make lying promises.' No 'if'. Kant held that moral duties bind every rational person, whatever they happen to want.
Check yourself
Kaveh sometimes slips through the metro gate without paying. 'One fare makes no difference to anyone,' he says. How would Kant judge it?
- Fine, because the consequences of one unpaid fare are too tiny to matter
- Wrong only if he gets caught and ends up having to pay a fine
- Wrong: his rule only works because most people pay
- It depends on whether riding free makes Kaveh happier overall
Show the answer
Wrong: his rule only works because most people pay
Right. His maxim, 'ride free when it's convenient', only works because most people pay. Kant's test catches exactly this: a rule you need others not to follow.
THE SECOND TEST
People are never just tools
Kant gave another version of the same imperative: treat people, yourself included, always as ends, never merely as means. Every person has their own goals and the right to choose. The key word is merely. You rely on others all the time. What's wrong is using someone in a way they couldn't agree to, which usually means deceiving or forcing them.
You use a taxi driver to get home, but not merely: he agreed to the trip and you pay the fare. Pretending to be someone's friend to get at their contacts treats them as a tool, because they'd never agree if they knew.
Check yourself
Which of these treat someone merely as a means, in Kant's sense?
- Faking friendship with a colleague so she'll cover your shifts
- Hiring a plumber and paying the price you agreed
- Hiding a car's accident history from a buyer
- Openly asking a teacher for a reference letter
- Pressuring a younger cousin to lie for you
- Asking a friend for a lift, and she's free to say no
Show the answer
Merely a means: Faking friendship with a colleague so she'll cover your shifts, Hiding a car's accident history from a buyer, Pressuring a younger cousin to lie for you
Respects them as a person: Hiring a plumber and paying the price you agreed, Openly asking a teacher for a reference letter, Asking a friend for a lift, and she's free to say no
THE MAIN OBJECTION
The murderer at the door
Kant held that lying is always wrong. In a late essay he even said you may not lie to a would-be murderer who asks where your friend is hiding. Most readers find that too rigid: duties can clash, and a rule that ignores consequences entirely can demand something terrible. Critics also ask how Kant settles conflicts between two duties, like honesty and protecting someone.
Many later Kantians push back from inside the theory: a maxim like 'lie to protect an innocent person from a killer' may pass the universal-law test after all, and the murderer, not you, is the one treating people as tools.
Check yourself
Darya's cousin is applying for a scholarship. He asks Darya, who works at a company, to write a letter saying he interned there. He never did. 'Nobody gets hurt,' he says. What would Kant say?
- Write it: helping family is a duty, and that outweighs one small untruth on paper
- Refuse: fake letters can't be universalised, and it deceives the committee
- Write it, as long as nobody on the committee is likely to check the facts
- Refuse, but only because she could lose her own job if it ever came out
Show the answer
Refuse: fake letters can't be universalised, and it deceives the committee
Yes. Both tests fail. Universalised, fake letters destroy the trust letters depend on, and the committee is being steered by a lie it would never accept.
Kant's check in three steps
- Write your maxim
Be honest about it: 'When I'm short of time, I'll copy a classmate's answers to get the grade.'
- Universalise it
Imagine everyone acting on it. Does the practice still work? Could you sincerely want that world?
- Check the people
Am I deceiving or forcing anyone? Would they agree if they knew exactly what I'm doing?
Check yourself
Match each situation to the Kantian idea it shows
Show the answer
- Giving correct change only because honesty is good for sales → In line with duty, but not from duty
- 'If you want to lose weight, cut sugar' → A hypothetical imperative
- 'Everyone skips fares, so there's no metro' → A maxim that fails the universal-law test
- Befriending someone just for their contacts → Treating a person merely as a means
- Refusing to lie even to save a friend from a killer → What critics call too rigid
Lesson recap
- For Kant, moral worth comes from acting from duty, doing right because it's right, not from the results.
- Universal-law test: could everyone act on your maxim? If it only works because others don't, it's wrong.
- Humanity test: never treat people merely as tools; deception and force are the warning signs.
- Main objection: absolute rules can clash and ignore disaster, as in the murderer at the door.