an ounce of sense/truth/decency etc
From Longman Dictionary of Contemporary Englishan ounce of sense/truth/decency etcan ounce of sense/truth/decency etcNONE/NOTHINGany sense, truth etc at all If you had an ounce of sense you wouldn’t believe him! → ounceExamples from the Corpusan ounce of sense/truth/decency etc• Anyone with an ounce of sense knows that results depend on factors other than staff efficiency. - T. Baines, Oxford.