The placebo is about feeling better not being better, and there is no way to measure how good it is going to be. There is no way to measure how bad it is going to be either. Nobody says a placebo is perfect. We can get worse in some ways. Plus if we stay the same in some ways and this goes on too long, that is reason enough to worry.
While we may administer our own placebo, it is never purely self-administered. Also, somebody can try to administer it to us. In either case, it needs others to confirm it and go along with it.
One form of the placebo that is rarely examined, is how we imagine that a moral law is interested in us and our wellbeing for this makes us feel special and protected. We want moral law and moral principle to be some kind of shield around us.
Think of the criminal law as an illustration. We know it does not do as much for a person as we would hope but at least it is there and we get some feeling of safety from that. It is the same idea. We want that for ourselves and our loved ones.
In religion, you hear that killing the innocent is always wrong as is adultery. Those are two good examples.
But those moral decrees would be irrelevant, if all or most, attackers were possessed by some force and were essentially innocent. Or if everybody was forced at gunpoint to sleep with somebody other than their spouse. Life is messy. It is complex. We have to do necessary evils, or evils that we at least guess are unavoidable, every day.
The decrees only apply if people have full free will, if nothing is pushing them. If your evil deed were 20% something and the rest of it was you, your choice, while you might be made accountable for murder or adultery, it would not mean much. Leniency would be needed for nobody knows if it is really 20%. A slap on the wrist then!
We don't want an objective morality that is too liberal and treats bad people as excused or near-excused.
Strangely enough, many people promote a loving God that leads to careless morality Big claims should not be believed lightly. And we are asked to hold that a person who says they are forgiven by God, is in fact pardoned and now being helped by him to become more moral. We are asked to act as if God is working more in that person's life than it seems for a sin is nothing compared to God.
There are serious differences between objective moralists.
For example, there people who "know" a wife should be burned on her husband's funeral pyre alive and who are more convinced than you are that stealing is always wrong.
Another, Catholic doctrine is that the Eucharist, the body of Christ under the species of bread, needs saving from a church fire even if it means leaving a baby behind to burn.
Nobody can logically prove their morals are more than beliefs and actually known to be true. Instinct is talking, not proof.
And as even God would not be a sinner if for some reason he had to preach what was untrue, it does not follow that if he implants a moral sense in you that it is objectively correct.
There are too many assumptions and contradictions in the objective morality outlook.
It will be replied that our being disastrous in discerning objective morality, does not mean that objective morality is a fiction.
True. It is also true that our not seeing Godzilla does not mean he is a fiction. Objective morality has a greater crop of problems than Godzilla. It is safe to assume that it should be treated as unimportant though possible.
Objective morality should matter hugely but it cannot therefore it is likely that it is a fiction and morality is subjective and arises from feelings and subjective impulses.
Let us consider the moral argument for God.
PREMISE 1 If God does not exist, objective moral values and duties do not exist.
PREMISE 2 Objective moral values and duties do exist.
CONCLUSION Therefore, God exists.
We will find that it is invalid and incorrect.
The first premise is a metaphysical claim, not an assumption of God's existence. It asks: “What would ground objective morality if God didn’t exist?” So that is okay.
The claim that the argument isn’t circular for it starts with widely shared moral experiences, not the assumption of God, is where it comes apart. They are feelings and shadows mistaken for experiences. We have just proven that. We are lying about how important objective morality would be, and trying to assign it more clarity, relevance and significance than it has. We want it to be our version. We actually oppose objective morality if it is not what we want it to be.
It is grounded on a wish to get away from, "Morality is whatever a person feels they want it to be". There is emotional pressure to present and support the argument. It is not really an argument in that sense. A God who wants us to work out that we need him would not let us be pushed that much. But we are.
It ignores how if we live in a virtually endless physical web and a web of spiritual realities, it is complicated and we might not get the neat simple morality we want. And we do not.
CONCLUSION
Objective morality, as popularly conceived, is based more on comfort than truth. Many, perhaps virtually all, may just care about the comfort. The wish to have a placebo, wherever we find it, drives us and it cannot be avoided. That alone would make our interest in objective morality suspect. But there is more. Whether we have an impulse to deploy the placebo or not, objective morality has the hallmarks of a placebo. The idea that moral law is law and law protects is the attraction.