Humans, theist or atheist, are innate to have the same capacity for decency and empathy. Same mechanics of emotions. The difference is that theists by logic, believe in the sanctity and dignity due a human life, being made in the image of God. Atheists, on the other hand, believe in some cosmic obligation of empathy towards agglutinations of organic material. Then antitheists will come around and claim how atheism will be a better incentive for decency and compassion.