The classical version of utilitarianism says simply to improve the greatest happiness of the greatest number.  A version recognising how that leads to chaos says the key is to think of virtuous happiness not just any happiness.

Ideal Utilitarianism says that we must maximise good happiness or happiness that does not rejoice in evil. It tells us to have good intentions when we act and it forbids evil thoughts despite the happiness they bring us. 

Ideal Utilitarianism would forbid you to increase happiness by keeping slaves or advocating slavery.

It says you should not freely tell a needless lie to maximise happiness because that is asking people to be grateful for your availing of evil. But what if they don’t know it’s a lie? The theory says you have to be sincere but you don’t have to be right for you cannot always be right. That injects it with a heavy dose of liberalism.

The ideal Utilitarianism theory will allow lying to prevent a greater evil for it is a consequentalist theory.
The theory recognises some acts as evil forbidding you to rejoice in them. Lies are evil for they are opposed to what is real. Slavery is evil for all should be regarded as equals. Ethical theories, which permit these things, do not claim that they are good but that they are regrettable evils that are needed to further a greater good.
Ideal Utilitarianism will allow you to enjoy the results of this evil on the grounds that you had to lie and so the evil opportunity was forced on you by necessity. It will allow you to commit and enjoy adultery for the same reason. It will argue that enjoying the results is not the same as enjoying the lie that was told in order to get the results.
To this I say, if we are to like the results and enjoy them, then whether the evil deployed is necessary or not is irrelevant.
The theory only allows you to work for good happiness. But what is more important: good or the happiness? If it is the good then happiness is less important. If it is the happiness then indeed we should rejoice in evil. To say we must work for only good happiness is really saying goodness comes first when there is a conflict.
If happiness is good that implies that you can rejoice in the evils you have benefited from for they are done now and cannot be undone.  Whether they were necessary evils or wanton evils is irrelevant. The point is they are in the past.

The theory is accused of having no concern for those who like evil and can only be happy if they have slaves. Its believers will preach to them and hope to convert them.

The theory makes calculations of what makes the most the happiest a bit handier for it reduces the number of people you have to take into consideration. It says that those you know well and believe to be good sincere people have to come before strangers whom you don’t know which makes it easier again.

Consequentalist ethics tends to hold that its okay to abort and rob a baby to be of future happiness. Some say that if the greatest happiness is what matters then the baby should be brought into the world. But Utilitarianism in all its forms is about the people that are here. It is about the practical and what has happened and what is happening to make a better future.

The Ideal theory answers the problem of how it could be wrong if a gang steal your television set when they get more happiness for it than you. The happiness is bad for it is celebrating evil.

It says that secret evil would have to be bad for it is talking pleasure in evil.

The theory can be improved further by amending it to, “Advance the greatest good happiness but only when you have reduced the greatest suffering first.” Ending suffering is more important than maximising happiness.

Ideal Utilitarianism is a vast improvement on Utilitarianism. Is Ideal Utilitarianism the best of the consequentalist theories and therefore the right one?

Some say they believe in a new theory called Preference Utilitarianism (page 94, Practical Ethics). According to this instead of maximising the greatest happiness of as many people as possible you work out what people would prefer and do what the greatest number prefer. That is fine but I don’t believe this is a new form of Utilitarianism at all for you cannot maximise happiness without giving people the happiness they prefer. You don’t give the majority an opportunity to enjoy a sex orgy for many of them will prefer to have sex with their own partner.

If Ideal Utilitarianism is true then we should either maximise our own happiness or that of others or both. Maximising that of others at the expense of your own, would be altruism and altruism is twisted and a caricature of love. Maximising your own would be egoism (serving others and yourself to feel good) or egotism (when it is about yourself regardless of others).
Altruism is unacceptable which would imply that we should only worry about ourselves and not other people though if we do this properly we will benefit others which is egoism. Egotism isn’t an option.

Ideal Utilitarianism fails to see that we should enjoy nothing for there is hardly anything that is not a necessary evil. For example, entertainment is evil for you could be among the starving poor feeding their babies and you are able to be entertained because they suffer without you. When you get a job it is stopping somebody else from getting it. You are judging that your need is greater than theirs and who are you to decide that?

When I am most sure I exist than that others do, I should be more interested in my own good happiness than in theirs. They want me to be happy with them as equals or in other words, they want me to make them happy and see us all as equals rather than in terms of my happiness being more important. The solution to this problem is that I cannot help it if I am most sure so everybody has to understand and accept and respect that. They must encourage me to put myself first. But that cannot be done unless I act as if I consider them as important as I am. I cannot be happy as an island. Thus my attitude that I am all that matters will
not stop me from treating them as well as I would if I regarded them as equals.
Ideal Utilitarianism has to bring this knowledge to the fore. Otherwise I may fail to reconcile the fact that I alone matter with the fact that I need to treat others well. Trouble and inner conflict will result.
It is dishonest yes to treat others as equals when that is not how you can think of them. But it is necessary to avoid the greater dishonesty that will result if I think I must behave as if there is nobody else around with feelings. The bad side is not your fault and there is no alternative thus you are paradoxically good in serving others despite valuing yourself first and foremost. As I am at the heart of my good conduct it becomes easier and more natural.

Ideal Utilitarian theory says that happiness is not good in itself for it is being happy about good and because of good that makes it good. So avoiding evils like lying or violence must be more important than happiness. This means that they have to be avoided totally and the happiness they bring will be turned into sadness. We cannot live in peace if we do that. Life is a choice of one evil over another.

The theory is incoherent for it says that lying and violence are worse than unhappiness and still it seeks to make an absolute value out of good happiness.

The theory cannot allow forgiveness for forgiveness is giving a person what they do not deserve. You cannot deserve to be pardoned for you deserve punishment. You cannot forgive a person unless they don’t deserve it. Forgiveness implies that you ought to be punished in the retributive sense. You cannot hold anything against a person you wish to reform or deter from evil. So forgiveness and being forgiving is celebrating the evil of forgiveness and the injustice so it is contrary to Ideal Utilitarianism.

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