Deontologists hold that the consequences of an action are often beyond our control, and so can have nothing to do with the moral worth of an action.
Instead, moral worth must derive from some intrinsic quality of actions. This means that certain actions are simply inherently wrong, and it is our duty to avoid them. Others are inherently good.
For Kant, the moral rightness of an action comes from the intentions of the moral agent.
Kant believed that through reason, we could uncover moral principles - so we can have a priori awareness of our duties.
If we based our morality on a posteriori reflection, principles would not necessarily be universally binding (they might be contingent on culture and context).
But by basing morality on reason, not only do we guarantee its authority - to break moral rules is, effectively, to commit a logical error.
The Good Will
According to Kant, the 'good will' is the key to intrinsic goodness - it is the only thing which is good in itself. All other motives - compassion, pity, honour - have the potential to be pressed into evil deeds.
If a person acts on their good will, then even if they continually make moral mistakes, forever bringing about negative consequences in spite of their attempts to do the right thing, Kant claimed that their good will would shine through as an indicator of genuine moral goodness.
Duty Versus Inclination
For Kant, the only motive with any worth is duty.
It is possible for two people to perform identical acts, with only one being morally praiseworthy.
For example - a shopkeeper who always gives correct change out of fear of being caught or losing customers, or even one who does the same out of an inclination towards honesty, would not be performing a moral action. Conversely, a shopkeeper who - even if he despised his customers - gave the right change out of a sense of duty, would be morally praiseworthy.
The Categorical Imperative
If duty is the key to morality, how do we know our duties? Kant claimed this was by formulating moral principles, or 'maxims'.
We identify these maxims through the categorical imperative.
First, these maxims must be categorical, not hypothetical imperatives:
A hypothetical imperative is conditional - eg. 'If you want x, do y.'
Categorical imperatives are uncondtional - eg. 'do y'.
Only categorical imperatives can count as maxims, because hypothetical imperatives are binding only if you want to attain a certain end.
'The Categorical Imperative' was…