>>535255
"Following your conscience" means that you do what you, based not on your wishes, emotions and feelings, but on what you conclude using reason and logic, believe is the moral choice; anyone who goes against their right judgment sins, because they knowingly choose evil.
Similarly, a person who concludes that he is under a moral obligation to do something, ought to do this, even if their logic turns out to be erroneous and in fact the other thing should have been done: such a person, when faced with choice between good and evil, chose good, although he was without guilt on his own part mistaken about which choice is in fact good and which is in fact evil.
Invincible ignorance of evil does not save you though - it only prevents you from the punishment you would have otherwise received for doing the particular thing whose evil you were invincibly ignorant of. You can still be punished for your other evil works.
Invincible ignorance ceases to exist when the person with it learns about their choice's evil - if they continue to act as if it was moral, they sin. A Hindu or an atheist, who knows or reasonably suspects (and doesn't try to solve the question) he does wrong, isn't invincibly ignorant and sins. Included here is voluntary, vincible ignorance too.