I don't see how lying about anything could be considered ethical. It may be socially acceptable to lie about yourself, but that doesn't make it ethical. Plenty

I don't see how lying about anything could be considered ethical. It may be socially acceptable to lie about yourself, but that doesn't make it ethical. Plenty of things that are socially acceptable are in fact profoundly unethical. So, the line is in fact very simple: if you are an ethical person, you never lie. Update: however, upon reflection, society forces us into practical considerations. If you avoid lying you will be taken advantage of because you weaken your position in society. For that reason, while lying is never ethical, it is sometimes the only realistic alternative. You may for example have people lying about being hiv-positive to get a job. There is no rational reason in many job categories to reject such an applicant, but in practice they won't get a job if they tell the truth. I also would make an exception for withholding the whole truth. Sometimes people have the right not to know things which would only hurt their feelings and bring no practical benefit.