No Chinese input at work, bear my English writting please.
A human is just a live creature controled by nerves and brain. Do you think that your nerves are spiritually good or bad? No good, no bad. When you say good or bad, you are talking the behaviors in a group setting or a social setting. The group is self-regulated to make the group survive. There comes the good or the bad. It means good or bad for the group, not for the individual. A crazy man kills another human, it appears to be evil to the group/society, but it may relieve some pain from the individual to make his/her more strong to survive. Then, it's good for the individual.
People LEARN the good and bad for the society when growing up.