Not all human actions involve a moral element. If I turn over in my sleep or sneeze, the turn or the sneeze is the act of a human being (actus hominis), but it is not a humane or moral act (actus humanus). Moral acts are not simply acts performed by a human agent, but also are acts that involve human will and intention.
In fact the character and moral quality of a moral act is determined by the intention of the agent. If I pick up an umbrella thinking that it is mine, I have not committed an act of theft, even if in fact the umbrella belongs to someone else and simply looks like my umbrella. My intention was innocent and no blame attaches to my action, though objectively I have taken what was not mine.
Likewise an action may involve an objectively innocent deed and still be subjectively wrong due to a bad intention. Suppose a football team is giving a free cap with the team logo to every person who attends a given game. Suppose I do not know about the cap give-away, very much want a cap, and take one furtively. In that case I have intended to steal something. The fact that I objectively did something that was permitted and that did not involve theft does not change my bad intention. If I intend an act of theft, I am morally, though perhaps not legally, at fault, even if by some odd circumstance it turns out that I owned or had a right to the object in question. Our intentions may be faulty or mistaken, but the rightness or wrongness of action is determined by those intentions.
In traditional moral terms, the principle made by these examples is asserted by this statement: the intention of the agent is the form of a moral act. The intention is what makes a moral act what it is, whether good or bad or indifferent.
Conscience (syneidesis) is the agent’s judgement concerning the rightness or wrongness of his moral acts. If, therefore, I do that which I judge to be right, then my act is morally good. From these ideas come the apparently odd conclusion that sometimes I am morally obliged to do that which is in fact wrong and bad. To understand this conclusion, it is necessary to explain further the difference between the subjective and the objective quality of moral acts and the problem of an erring conscience. In this article we will consider primarily the subjective authority of conscience.
Already in the above examples involving taking an umbrella and a cap, we see that the actual, objective right to take something is somewhat separate from my fallible and often mistaken understanding of that right. I may think I have a right to something when in fact I do not, or I may think I do not have a right to something when in fact I do. My subjective, personal understanding of that matter can be mistaken and may differ from the objective, actual state of things. My intention is necessarily subjective and personal. It follows that there can be a difference between what I intend and what is in fact the case or between the subjective and objective situation.
If I am considering an action with a moral dimension, I am always obliged to do what I think is right. If I do not do what I think is right, then I am doing what I think is wrong, and that is always unjustifiable. It is conscience which judges a contemplated act to be good or bad. I am, therefore, always obliged to follow my conscience and to do that which I believe is right. From this obligation we may conclude that conscience is subjectively infallible. As a general rule, if I do what I believe to be right, then I have done nothing that is wrong or morally blamable and I am subjectively in the right. I may in fact actually and objectively do something that is wrong, while being subjectively in the right. We must always follow our conscience. Not only is conscience subjectively infallible, it is the chief and greatest subjective moral norm or rule or law. Here is an infallible and exceptionless moral law: Always do what you believe to be right.
Nonetheless, we know that we often are in fact mistaken. The authority of conscience is subjective but may be objectively wrong. Conscience is the chief subjective norm or rule or law, but we also are subject to objective norms and rules and laws. To emphasize the authority of conscience and the respect that we should give to the conscientious acts of others is not the only thing to say about the authority of conscience. Many moral acts are actually and objectively ‘defective’ in that they violate objective moral norms and result in actual harm. Therefore, after emphasizing the subjective moral authority of conscience, we next should consider other matters. These matters include the duty of the moral agent to instruct and form his conscience properly. Simply feeling that I would like to do something, to perform a particular act, does not make that act conscientious. There are acts made in bad conscience, acts made without proper consideration, and actors who have refused to consider relevant laws and circumstances that affect a particular act.
In short, not every moral act is an act in good conscience.