Referring to the criterion of "absolute reasonable and conventional human being" as if it was made only by looking at an adult man without skills, cannot be a correct indicator of inference in many cases of responsibility where differences and capabilities are seen in the middle of it. Guilt, as a result; be assumed to bear or negate the responsibility. In the meantime, it is necessary to pay attention to the differences and capabilities, and based on them, free the above criteria from this absolutism. An effective step has been taken regarding the necessity of a relative view in this regard: "responsibility for actions based on skill and knowledge" in English law. in that country; Regarding that particular type of responsibility and for inferring fault or negating it, focusing on the general criterion of "reasonable and conventional human being", the criterion of "reasonable skill and care" has been used, and based on this criterion; Anyone who does not have reasonable skills or does not show reasonable care of himself despite having such ability is considered responsible. To explain this criterion in the following article, the author has used the descriptive-normative research method and based on the judicial opinions issued in the English courts, the existence of the duty of care also; It describes reasonable skill and care.