见利忘义

jiànlì-wàngyì

[forget morality and justice when one sees money; be actuated by mercenary views; forsake good for the sake of gold] 只图一己私利, 而置道义于不顾

某与吕布同乡知其有勇无谋, 见利忘义, 某凭三寸不烂之舌, 说吕布拱手来降。 --罗贯中《三国演义》