You may not always realize sin as you are doing it, but you have the capability of realizing it. Many factors prevent you from avoiding sin, but your conscience is what knows right from wrong.
I have no doubt that you are capable of telling right from wrong, therefore you are capable of sin.
Now, the mentally challenged or the very young do not have this capacity.
SD
I think conscience in unconverted people is simply a conditioned response. Look at a child. It would take other peoples things all day if you never taught it that taking things from others is wrong. Conscience in the converted is the conviction of the holy spirit.
I have no doubt that you are capable of telling right from wrong, therefore you are capable of sin.
Now, the mentally challenged or the very young do not have this capacity.
Which of course is the entire argument for infant baptism not being effective in the "saving" of an infant. Since they have no ability to repent from sin, they are still in unrepentent sin.