Is man born with an inherent sense of right and wrong from God? How far does environment affect our sense of judgment and preferences? If we were never taught, would we have an idea of how to make our decisions? Do ALL humans, not just Christians, have a sense of inherent good Like a signature of God on us as His creation?
There is no doubt that environment does affect one's decision on what is right and wrong. Children of abusive parents tend to be abusive themselves; children raised in broken homes do not value much the meaning of a family. However, the Holy Bible gives many examples of good people who had evil children and vice versa. Samuel the prophet was a righteous man but his sons did not follow his ways "Now it came to pass when Samuel was old that he made his sons judges over Israel...But his sons did not walk in his ways; they turned aside after dishonest gain, took bribes, and perverted justice" (1 Sam 8:1-3). On the other hand, while the Holy Bible says about King Ahaz "King Ahaz became increasingly unfaithful to the Lord, he sacrificed to the gods of Damascus …he provoked to anger the Lord God of his fathers" (2 Chron 28:22-25), it says about his own son Hezekiah "And he did what was right in the sight of the Lord, according to all that his father David had done" (2 Chron 29:2).
If environment were the sole factor in shaping our personalities and influencing our decisions, then free will and knowledge of good and evil would not exist. God gives everyone the chance to know Him because we know that He wants everyone to be saved.
St. Paul describes this situation of people who do not have the law of God saying, "For as many as have sinned without law will also perish without law, and as many as have sinned in the law will be judged by the law" (Rom 2:12). "For when Gentiles, who do not have the law, by nature do the things in the law, these, although not having the law, are a law to themselves, who show the work of the law written in their hearts, their conscience also bearing witness, and between themselves their thoughts accusing or else excusing them" (Rom 2:14-15). So by nature individuals can do the things of the law as enticed by their conscience.