For those who have knowledge knowledge can be added to them, but those who have no morality even knowledge cannot be added to them. The meaning of this sentence was that people with knowledge could improve their quality and ability through continuous learning and accumulation. People with moral defects could not make up for their shortcomings even if they had a lot of knowledge. This is because morality is an inner belief based on values and codes of conduct. It is the embodiment of human nature and inner cultivation, and cannot be changed by external knowledge. Therefore, even if a person with incomplete morals has a lot of knowledge, he can't really understand and apply it because it doesn't conform to moral principles.