Deontological ethics is the ethical theory that is rule, based, and the term is taken from the Greek word deon, which means "duty". It claims that morality lies in one's conforming to his duties and obligations rather than in the act of seeking good results. The most well, known advocate of this approach was Immanuel Kant, who believed that moral laws should be universal and unconditional.

Principles

Duty over Consequences: Whether an action is right or wrong is determined by its accordance with moral principles, not by the results it brings.

Universalizability: A moral principle has to be valid for everyone at all times. If lying is considered wrong, then it is wrong for everyone, in every situation.

Respect for Persons: People should always be seen as an end in themselves, and never as a means to an end.

Moral Absolutes: Some behaviors such as killing or stealing are always wrong irrespective of the situation.

Strengths

Clarity and consistency: Deliver a clear set of norms for ethical behavior.

Human dignity: Ensure the protection of people against being used as mere means to a higher end.

Moral responsibility: Fosters an understanding of accountability through the emphasis on good will and duty.

Criticisms and Challenges

Rigidity: Following rules too strictly can cause morally disturbing situations (e.g., not lying even to save a life).

Conflict of duties: What if two duties conflict, for example, the duty to tell the truth and the duty to protect others?

Lack of flexibility: Critics say it is insensible to ignore the context and the consequences in practice.

Conclusion 

Basically, deontological ethics is a moral compass that keeps us focused on the principles and duties that underlie human dignity, rather than just outcomes. At times, it can be a bit inflexible, yet the way it sticks to the idea of universal moral rules offers a solid base for justice and fairness.

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