But there may be problems with our conscience that we're unaware of, and which originate in childhood; particularly with parents or authority figures who rule over us. The culture we grow up in is never perfect, and often great damage is done to us from our first days of childhood. Early experiences are crucial in the development of conscience.
Eastern cultures are, more often than not, shame based. From very early days children are taught to feel terrible shame for failure of any kind, and also that some failures can never be forgiven or expunged. What is seen to be good for the group takes total precedence over the individual. Individual competitiveness is discouraged. The Japanese teach their children that, "The nail that sticks up gets hammered down." Suicide is a major problem in shame based cultures, because forgiveness is rare.
Muslim women in the Middle East are typically required by Sharia Law to undergo genital mutilation, a practice too shocking for this author to describe. (Here's a link). If they refuse the procedure they're shamed and shunned. No one will marry them. Even if they're forcibly raped, entirely against their will, they're treated as guilty adulteresses. Men are often excused from guilt because they're seen as having been tricked by the woman.
In the western world, individual and family competitiveness take precedence over all other groups. President John F. Kennedy grew up in a famous Boston Irish family with a successful and powerful father. Joseph Kennedy drilled and regimented his wife and family into a merciless sense of competition, with each other and the world. Not only were they expected to excel, they had to win, and often. Losing was considered almost shameful, even fatal. Cheating with cleverness was admired or at least not discouraged, depending on the outcome. The Scots, Irish, and English sometimes took this style of child rearing to heart as a positive good. Thus they dominated the world for over a century with their empire.
Parents need to teach us hundreds of rules and behavioral standards so we can get along with them and others in the family and community. They do this according to their own upbringing, and appeal to our awareness of good and bad, such as it is. The fear of making parents unhappy is a powerful motivator if we love and admire them. The fear of punishment and pain will motivate us if we don't. Good parents will follow their rules and set an example. They'll chastise and punish us fairly for doing wrong, or praise and reward us for doing rightly. Bad parents will often ignore their own rules and our bad behavior for too long, then explode with rage when a certain threshold is reached. Or they'll be excessively petty, controlling, and unforgiving of the slightest transgression. The big question is who taught them right and wrong, if anybody did?
The combined understanding of all our cultural behavior standards often passes for conscience. But it really isn't conscience. It's more like a loyalty oath, and oaths can be terrible weapons for evil.
From early human civilization all the way up to our day, religions and political groups of all kinds have required oaths that force us to pledge our lives and fortunes to causes which are sometimes amoral. Corrupt leaders frequently appeal to their subjects' "conscience" when demanding that they commit horrific crimes. Nazi SS chief Heinrich Himmler famously did this to speed up the Final Solution, the national plan to exterminate over six million "undesirables" (Link).
Of course, what is moral to one person may not be to another. Everything depends on the origin of moral laws. Atheists claim that reason alone can guide us to what is moral, but reason is an ever-changing thing, according to what is expedient.
Judaeo-Christians know that God, from the foundation of Creation, gave us moral guideposts that are eternal and unchanging.
Fact is, only God can judge us and others. We don't have knowledge or wisdom enough to do it.
"There is only one Lawgiver and Judge; the one who is able to save or destroy. But you, who are you to judge your neighbor?" [or yourself?] - James 4:12.
A true conscience is a gift from our Creator, and it stands apart from our culture, the world, and time. It can be refined by us through the application of prayer and reason. Conscience is like our smartphone, an instrument through which God can speak to us. It must be cared for, charged up, and kept close to us. No earthly power can dominate or succeed in corrupting us if we have true conscience. But a defective conscience will doom us to eternal damnation.
"To the pure all things are pure, but to the defiled and unbelieving, nothing is pure; but both their minds and their consciences are defiled." - Titus 1:15 (Link)