Mill would might respond to Arnold one of 2 ways. First, he might say that while pain might sometimes be an instrumental good, it is not a good in itself (unlike pleasure). Therefore, pain cannot be pleasure. Second, he might respond that Arnold is confused. He seems to be saying that, for him, growing is a good in itself. But would Arnold pursue growth if it didn't bring him pleasure? Probably not. So, it is not growth that is the good in itself, but the pleasure that Arnold gets from growth.
Arnold, you are a great man in many respects, but a logician you are not.
In the chapter of Utilitarianism titled "What Utilitarianism Is" Mill replies to a series of common misunderstandings and criticisms directed at utilitarianism.
1. Objection: Damn fools be confusin' what utilitarians mean by 'utility'.
Reply: Utility is not something different from pleasure but "pleasure itself, together with exemption from pain".
Clarification: Definition of Utilitarianism/Greatest Happiness Principle: Actions are right in proportion as they tend to promote happiness, wrong as they tend to produce the reverse of happiness. Happiness means the same as pleasure and absence of pain. Unhappiness is pain and privation of pleasure. Morality is founded on the principle that "pleasure, and freedom from pain, are the only things desirable as ends; and that all desirable things are desirable either for the pleasure inherent in themselves, or as means to the promotion of pleasure and the prevention of pain."
Issue: Mill thinks that we ought to act on the greatest happiness principle because it brings about 'good' consequences. However, one might contend that morality involves what is right, not necessarily what is good. Are rightness and goodness one and the same?
2. Objection: Utilitarianism is the doctrine worthy only of swine--there are nobler objects of pursuit for humans other than mere satisfaction of pleasure.
Reply: Ah ha! It's not the utilitarians but their critics who represent the human condition in a degrading light. The critics assume that human beings are only capable of the same pleasures that humans are capable of. But surely the pleasures that would fully satisfy a beast would not satisfy a human being's conception of happiness. Humans also have pleasures of the intellect, imagination, and moral sentiments which animals don't have.
Mill's Qualitative Hedonism: No inconsistency arises in utilitarianism by saying there are distinct kinds of pleasures, some of which are more desirable and more valuable than others. In other words, there's no good reason to suppose that pleasure is all of one type and can only be measured in terms of quantity and intensity. There are higher (i.e., intellectual) and lower (i.e., bodily) pleasures.
Ok, but how do you decide why one type of pleasure is higher and another lower? It seems kind of arbitrary...Here's how you dooz it: If a majority of people who have experienced and are able to understand and appreciate both kinds of pleasures have a preference for one, then the preferred one has the higher ranking. To determine different kinds of pleasure you'd run the same test but if the majority wouldn't trade a small amount of one type of pleasure for any amount of the other, then you have 2 different kinds of pleasure (high and low). It seems as though, in theory, you could have lexical scale of kinds of pleasures.
For example: Suppose we want to compare the pleasure we get from being on facebook to writing an 'A' paper. If the majority of people who have done both wouldn't trade even a small quantity of the 'A'-paper feeling for a ton of time on facebook, then we could say that the kind of pleasure you get from being on facebook and the kind of you get from writing an 'A' paper are qualitatively different. They are of distinct kinds.
People who are acquainted with both higher and lower types of pleasures prefer the higher pleasures: According to Mill this is an empirical fact. Part of his supporting evidence is that few humans would give up being human in exchange for being a fully satisfied pig and few well-educated people would give up their education for being a fully-satisfied ignoramuses (ignorami?). As Mill famously says,
[i]t is better to be a human being dissatisfied than a pig satisfied; better to be Socrates dissatisfied than a fool satisfied. And if the fool or the pig is of a different opinion, it is because they only know their own side of the question.
Rob Ford Counter-Reply: How do we explain people giving up long-term higher pleasures in favor of short-term lower pleasures? People can knowingly make bad choices. For example, we know we shouldn't be chronically checking facebook when we're supposed to be writing a paper or studying, but we do it anyway. The fact that we don't act on our knowledge is no indictment against the claim that we have the knowledge of what is good for us.
So, now that we've sorted out what utilitarians mean by 'utility' and that there are (at least) 2 distinct kinds of pleasure, lets look at some further objections that Mill deals with...
3. Objections from Kantian (aka deontological, aka transcendental) Ethics:
(a) Happiness cannot be the rational purpose of human life because (i) it isn't attainable and (ii) ain't nobody got a right to happiness.
Reply 1: Dude, even if you were right that happiness isn't attainable, which your aren't, the objection still wouldn't apply to the other half of the utilitarian doctrine--that utility also includes avoidance of pain and suffering. So, even if we can't attain happiness, rational action is still directed at avoiding and minimizing pain and suffering. Boom goes the dynamite.
Reply 2: You're wrong about the unattainability of happiness because you misunderstand what it is. Happiness is not just a "state of exalted pleasure" or "a life of rapture". No, my dear friend; by happiness we mean "an existence made up of few transitory pains, many and various pleasures, with a decided predominance of the active over the passive," and not expecting more from life than it can reasonably bestow.
(b) True nobility and virtue requires renunciation of one's own happiness.
Reply 1: You're all like "virtue and nobility require self-sacrifice blah, blah, blah". Yeah, OK, I get it. But check this out. Why would anyone sacrifice their own happiness? Go ahead, I bet you'll never guess. Give up? Cuz they're trying to make things better for other people. Maybe for their family or friends or community. Maybe they realize by sacrificing their own happiness they can make many more people happier or at least reduce their suffering.
Sure we call this virtuous behaviour...no doubt. But at the end of the day this only further confirms happiness as the supreme good because no one in their right mind would suffer and sacrifice their own well-being if they didn't think the consequence of this suffering would be an improvement in the well-being of others. The suffering itself is not a good, rather its consequences are. To voluntarily give up one's own happiness without the effect of improving the well-being of others is not virtuous, it's just plain loco...ese.
Clarification of Utilitarianism and the Principle of Impartiality: Don't get it twisted. Utilitarianism isn't about maximizing your own individual happiness at the expense of others. What makes an action right is that you impartially evaluate the sum total of happiness that several courses of action might produce and choose the one that creates the most--regardless of how it's distributed.
For example: Suppose you can do A or B. Action A will improve your own utility by 4 units but Action B will improve 5 other people's utility by 3 units, for a total of 15 units. You must make the decision from the point of view of a "strictly impartial" and "disinterested and benevolent spectator." The right choice, as prescribed by utilitarianism is B. You do not treat your own well being as of greater importance as the well being of others.
Practical Application of the Greatest Happiness Principle: (a) Laws and social arrangements should seek to harmonize the happiness/interests of the individual with the happiness/interests of the community. (b) Education and opinion should serve to teach people that their own individual happiness is bound up in the happiness of others.
4. Objections: The utilitarian standard is too high! It's unreasonable to expect people to consistently put their own happiness aside in favor of the happiness of others.
Reply (and criticism of Kant): First you said it was too low and now it's too high. Make of your freakin' mind people! 99 times out of hundred our own interest will align with what's also best for others. So long as we don't confuse motivation of action for the rule of action, utilitarianism is not too high a standard. Kant thinks that only an action's motive defines if the action is right. But this is wrong. The motive tells us about the moral worth of the agent, it does not tell us about the moral worth of the act.
If we want to know if the act is right, we look at the consequences of the act; if we want to know if the agent is good, we look at the intentions behind the act. Don't get 'em mixed up. Of course, good acts usually come from agents with good intentions and agents with bad intentions usually do bad things but it's not necessarily the case. Sometimes someone who intends to do good can cause harm and vice versa.
Criticism of Aristotle: A moral standard doesn't decide whether an act is good or bad based on whether the person who did it is good (i.e., virtuous) or bad. That's loco. Good (i.e., virtuous) people can sometimes do bad things just as non-virtuous people can sometimes do good things. Defining the action as good or bad in terms of the agent's moral character is loco.
ISSUE: What is morality about, the act or the intent behind the act? Or is it both? Or is it the agent's character?
5. Objection: It's just not practical to do a utility calculus every time we have to act in a moral situation. Sometimes there just isn't time or energy or the foresight to anticipate and calculate the utility calculus of each possible course of action.
Reply 1: That's just ridiculous. Ain't nobody sayin' we can't use Christianity as a guide for action because there isn't time to read the Torah and New Testament before each decision...
Reply 2: Besides, it's not like we're starting from scratch every time we have to make a decision. Each individual has a lifetime of experience and a wealth of social knowledge to draw on for rules of thumb. We learn what general principles tend to give the best utilitarian outcomes in like situations.
For example: It's not like you need to sit down and weigh the consequences of murder and stealing each time it crosses your mind, you've got secondary rules prohibiting these acts that already conform to the main principle. Duh!
We can use the first principle of utilitarianism to derive secondary (practical) principles of action. If, in a particular situation, the secondary principles conflict, we can resort back to the first principle to decide which secondary principle should take precedence.
Kinds of Utilitarianism Rule vs Act Utilitarianism: Ok, there's an extensive literature on this topic so I'm just going to give a brief outline.
(Simple) Act Utilitarianism: For each act, you must perform the utility calculus. Otherwise stated, for each act, you should judge its rightness or wrongness in terms of how much relative happiness is created (relative to other options or inaction).
Rule Utilitarianism (weak): We use secondary rules to make decisions. However, if we encounter a situation where the secondary rule dictates a course of action that doesn't maximize happiness, we temporarily suspend the rule in favor of the Greatest Happiness Principle. Under this type of rule utilitarianism, the secondary rules are heuristics, but can be suspended for special cases in which they don't give the right result.
Rule Utilitarianism (strong): Same as weak except the rules are never suspended. Suspending rules undermines predictability causing anxiety and uncertainty which, in turn, diminish utility.
Common Objections to Utilitarianism
A. It seems to commit us to doing things we consider to be immoral: For example, suppose there's a terrorist who's going to blow up half of Uzbekistan. The authorities have managed to capture his two children. The only way to convince him to give himself up is to threaten to kill his two sweet innocent children who have never even hurt a fly. In fact, it was reported that they have flies for pets and they treat them very well. Anyhow, we know that he doesn't believe that the authorities will harm his kids and that the only way to get him to believe it and turn himself in is to kill the first one.
Utilitarianism commits us to killing the first kid in order to save half of Uzbekistan. Although it might seem justified, killing innocent children hardly seems to be a moral act. Also, because the good is defined in terms of utility, utilitarianism call this action 'good'. But killing innocent kids (especially if they don't hurt flies) doesn't seem good...
B. The Experience Machine: Suppose it's the future. It is the year 2000. There are robots and flying cars everywhere and they both talk in robot voices. Neuroscientists have invented an experience machine...basically like the matrix. You can plug in and have any experience you want. You can have any the memories implanted too. You can choose to have the experience of climbing mount Everest. You'd have all the memories of the struggle along the way and the triumph at summit.
In fact, if you wanted, you could remain plugged into the machine forever and pre-program the exact life you want. You'd never know the difference. Would you choose to be plugged in forever?
Utilitarianism defines good in terms of pleasure (and absence of suffering). However, this thought experiment seems to show (if you answered no) that there's something more that we desire beyond mere pleasure.