Kant's categorical imperative

Unsurprisingly, past thinkers have explored a plethora of perspectives, and yet most of them have an essential aspect in common: They presuppose some general "good" as given, and thus serve mainly as guides designed to bring that to fruition. But not Kant. In the 18th century, he broke with that tradition and set out to find an approach that identifies what qualifies as "good" independent of prior assumptions. Kant viewed ethics as a scientific discipline, whose responsibility it is to reject all presuppositions that do not withstand an analysis of reason. His resulting approach is called the categorical imperative, which formally identifies maxims by which to orient one's behaviour—and thus the guiding rationality.

Kant formulates his categorical imperative in various phrasings (for specific domains), which generally explicate that any action should be guided by rules that do not cause contradictions if they were globally applied (meaning: if everybody followed the same principle, it would cause no problem). Importantly, this approach can be used from any starting point. It can be used for any behavioural contemplation—as long as it can be generalised—and any maxim can be put to the test. There is no ultimate rule above others, a notion that is indicative of Kant's underpinning interpretation of liberty. To Kant, humanity is destined to be free, with true (or "qualified") freedom achieved by following one's own rules. As representatives of this liberty, we all carry a duty of respect for each other, ultimately yielding the concept of human dignity (which is absolute, innate, and cannot be quantified against other things).

Ethical behaviour, after Kant, is thus only attained, if its guiding maxims are rational and non-contradictory, a definition confronted with two major points of criticism. First, some view the categorical imperative as overly clinical, detached from everyday life, "too formal". Humans, as Hegel pointed out, do not actually come to decisions after contemplating whether an action runs the risk of undermining itself, but by other motivations, such as our self-perception: We don't lie because we (want to continue to) see ourselves as trustworthy, not because lying (if suddenly globally applied) erodes language (as no statement could be trusted any longer). The second point of criticism highlights problems with the approach's usage in scenarios where ethical behaviour causes detrimental consequences. For example (originally by Constant), if a murderer asks me where a friend of mine hides, am I obligated to share this knowledge because lying is unethical?

Fortunately, the two points of criticism are somewhat misguided. The categorical imperative does not try to clarify how to act in any particular situation (which, to Kant, is always decided by one's conscience), nor does it compel any specific behaviour. Instead, Kant's approach should be viewed as an educational tool to find (rationally) reliable guiding principles in the first place—which can then be taught and cultivated. The found maxims, in theory, could then form rights: general, public standards, that everyone can exercise, but nobody must. Unsurprisingly, none of us are required to give up a friend; we can simply close the door instead.

Note that this is not a conclusive, or even necessarily correct interpretation. It is merely an attempt at summarising the provided script (that only touches on the topic briefly).