When people have to choose between two options that both feel wrong, they face a moral dilemma, a dilemma is a hard choice between two undesirable options. Face a dilemma is the standard formal wording (have a dilemma is fine in speech; meet a dilemma is not English). Alongside it, a moral obligation is a duty you are morally bound to fulfill, and your ethical principles are the moral rules you live by. All three are formal, neutral words used in serious, reasoned discussion.
Naming an ethical conflict
face a moral dilemma /feɪs ə ˈmɔrəl dɪˈlɛmə/ — Doctors often face a moral dilemma when a treatment might save one patient but harm another.
moral obligation /ˈmɔrəl ˌɑblɪˈɡeɪʃən/ — She felt she had a moral obligation to report what she had seen.
ethical principles /ˈɛθɪkəl ˈprɪnsəpəlz/ — Journalists are expected to follow ethical principles even under pressure.
Not ""He has a moral problem about lying to his friend." (too vague; it's a forced choice between two bad options)" — say ""He faces a moral dilemma about lying to his friend." (a genuine conflict between duties)". A dilemma is a choice between two undesirable options, and formal writing pairs it with face. 'Moral problem' misses that it's a hard, two-sided choice.
Try it: Which sentence uses the collocation correctly? (The nurse faced a moral dilemma when both patients needed the last bed. / The nurse met a moral dilemma when both patients needed the last bed. / The nurse got a moral dilemma when both patients needed the last bed.) Answer: The nurse faced a moral dilemma when both patients needed the last bed. — The fixed verb for a dilemma is 'face', and a forced choice between two patients is exactly a dilemma. 'Met a moral dilemma' isn't idiomatic English, and 'got a moral dilemma' treats it like an object you receive rather than a conflict you confront.
Universal rules and the greatest number
Something universal applies to everyone everywhere, without exception — not just to some people or one culture. A famous utilitarian idea is aiming for the greatest happiness for the greatest number of people, meaning as many individuals as possible; because people are countable, we say the greatest number, never the greatest amount. Something inherent belongs to a thing as an essential, built-in part that can't be taken away, so an inherent dignity is one a person simply has by being human. Keep inherent and universal apart: both are formal, but inherent describes what sits inside something, while universal describes how widely a rule reaches.
universal /ˌjunɪˈvɜrsəl/ — Kant believed that honesty was a universal moral law binding on everyone.
the greatest number /ðə ˈɡreɪtəst ˈnʌmbər/ — Utilitarians want the policy that brings the greatest good to the greatest number.
inherent /ɪnˈhɪrənt/ — Many argue that every person has an inherent dignity that cannot be taken away.
Not ""We should help the greatest amount of people." (people are countable, so 'amount' is wrong)" — say ""We should help the greatest number of people." (the standard utilitarian phrase)". Use number for countable nouns like people; 'amount' is for uncountable things like money or time. In philosophy the set phrase is always the greatest number.
Try it: A utilitarian wants a policy that benefits ___ of citizens. Which fits? (the greatest number / the greatest amount / the most general number) Answer: the greatest number — Citizens are countable, so 'the greatest number' is correct and it is the standard utilitarian phrase. 'The greatest amount' wrongly uses an uncountable quantifier for people, and 'the most general number' isn't an English collocation at all.
Try it: Which sentence uses 'universal' the way philosophers mean it? (A universal moral law is meant to apply to every person, without exception. / A universal moral law is one that most people happen to follow these days. / A universal moral law is a rule that applies only within one culture.) Answer: A universal moral law is meant to apply to every person, without exception. — 'Universal' means applying to all, everywhere, so 'every person, without exception' captures it. The 'most people happen to follow' option describes something merely common or general, and the 'only within one culture' option is the opposite of universal.