do no harm

Meanings

verbdo no harm (third-person singular simple present does no harm, present participle doing no harm, simple past did no harm, past participle done no harm)

present singular third person does no harm · participle present doing no harm · past did no harm · participle past done no harm

ethicsTo perform no actions which will be injurious or in any way unfavorable to another person, regardless of whether one does anything of positive benefit for that other person.
First, consider the moral minimum, do no harm.
2005, Patricia Illingworth, Trusting Medicine: The Moral Costs of Managed Care, Routledge, →ISBN, page 100
4 more examples
"Oh, make your mind easy! I shall do no harm, if I do no good."
1889, Wilkie Collins, chapter 51, in The Legacy of Cain
[G]et government out of the gambling business. . . . These officials pervert public policy, which should at least do no harm.
1999 March 29, William Safire, “Essay”, in New York Times, retrieved 18 Aug 2014
A doctor's principle code is, "First, do no harm."
2008 December 20, Judith D. Schwartz, “Making Hospitals Greener — and Patients Healthier”, in Time, retrieved 18 Aug 2014
Hence, some people consider non-maleficence to be the most basic of all the cardinal principles of ethics; it lays down the least minimum condition for ethical correctness, as if to say: "even if you would not do good, at least do no harm."
2012, A. Bame Nsamenang, editor, Handbook of African Educational Theories and Practices, →ISBN, page 100