• Eudaemonia - human flourishing or well-being.
• Arete - excellence or virtue.
• The Mean - the virtuous midpoint between two extremes.
• Magnanimity - greatness of spirit; “good” is the ultimate aim for all.

The core of Aristotle’s ethics revolves around the concept of eudaimonia, often translated as “flourishing” or “well-being,” rather than mere happiness.
In actuality, it means something closer to continuous self-realization.
Because Aristotle isn’t saying that you should be happy literally all the time. No, that would be too much, and therefore violate the mean.
Aristotle argues that the highest good achievable by human action is this state of flourishing, which he defines as “activity of the soul that expresses our goodness.”
This idea forms the foundation of his ethical framework: the goal of ethics is not just theoretical understanding but practical application in one’s life.

Aristotle’s doctrine of the mean is another central concept, proposing that virtue lies in a middle state between extremes of excess and deficiency.
The mean means something relative to us. It is determined by the context.
It is not that a very wealthy man will be forever more generous than a less wealthy man because he can quantitatively give more, but rather the proportion of the giving that makes the generosity.
It’s fine to be within some margin of the perfect middle. This is probably the best way to stay at the mean; to swing a little below and a little over, that is.

The book also speaks to the nature of virtue, distinguishing between intellectual virtues (developed through teaching) and moral virtues (developed through habit).
None of our moral virtues develop in us naturally. It takes effort.
You become virtuous through action.

Also, with every virtue, the things that give rise to it and develop it are the same things that can mess it up.

As you deal with other people, you might become fair and honest. But you also might become unfair and dishonest.
Your habits matter. Which way do they take you?

One of the most compelling aspects of the work is Aristotle’s practical approach to ethics.
He repeatedly stresses that the purpose of studying ethics is not merely to gain knowledge, but to become good people through action.
As he states, “Our goal in practical matters isn’t just to theorize about all the things we’re supposed to do, and know about them. Our real goal is to do them.”

One of the most striking aspects of the Nicomachean Ethics is its emphasis on personal responsibility.
Aristotle argues that being good or bad is up to us, as we choose our actions willingly.
He places the onus on individuals to cultivate virtue and strive for excellence.

In the beginning of the book, Aristotle lays out that “good” is what all things strive for.
The highest good is some (certain) goal we want for the sake of it, not because it serves something else. It’s the reason we want everything else we want.
Like a tree of goals: it’s the root.
And if we knew what that was, that’d be great for us, right? So we should try to figure it out.
If we have an aim, aren’t we more likely to hit what we ought?

Good things can harm us, too.
Too little or too much.
Virtues like courage, generosity, and temperance all lie on a spectrum between deficiency and excess. Both extremes are vices.
Too little courage is cowardice, too much is recklessness. The right is courage, which means to take a risk when it’s rational and necessary.

While reading, I was reflecting upon whether it’s possible to have too much wealth.
I’m not sure that it’s possible to have too much wealth. But it is possible to be corrupted by it, which seems to me to be the great danger there.
And likewise in having “too much” health. There is no such thing, for the instant it becomes a double-edged sword / it harms rather than hurts, it is no longer health. So instead, again, it seems to me that it is the individual whose pursuit of something becoming the singular focus of that individual which is harmful, not the thing itself.
For example, poison is not harmful if you do not ingest it. It is our actions, our judgment, our thoughts that make something good or bad.

While having wealth or health in itself is not a vice, the pursuit of these goods at the expense of everything else can lead to imbalance.
It’s not the thing itself that is too much or too little, it’s our relationship with it and how we let it shape our actions.
Courage that goes beyond reason ceases to be courage and becomes foolhardiness because it lacks the wisdom and judgment that should temper it.
Sacrificing yourself unnecessarily is not truly courageous, because it lacks the virtue of prudence, or practical wisdom.

When is something too much or too little? It changes its nature when it deviates from the mean. The virtue is always in balance, in harmony with reason and appropriate to the context.

People like that [with the right upbringing] either already have, or can easily grasp, [the right] principles. If neither of those applies to you … well, Hesiod says it best:

Best of them all is a man
who relies on his own understanding.
Next best, someone who knows
how to take good advice when he hears it.
So, if you’re clueless yourself,
and unwilling to listen to others,
taking to heart what they say –
then, sorry, you’re pretty much hopeless.

1. People who can rely on their own understanding
2. People who can take good advice when they hear it
3. People who can do neither

You certainly don’t want to be 3.

So that’s exactly the approach you need in other areas as well: never let the side issues become more important than the main tasks.

As they say, ‘the start is more than half the job’ – that’s to say, a lot of the things you’re trying to figure out immediately become clear once you have [the right] starting point.

So it turns out that flourishing is the best thing there is, and the most honourable, and the most enjoyable, and those three things are not incompatible, as the [famous] inscription on the temple at Delos implies they are:

The most honourable thing? To be righteous as can be.
But the best thing in life? To be healthy and hale.
But the sweetest thing is to get your heart’s desire.

Being a good person is enjoyable in itself.
For if you don’t enjoy being a good person, you cannot be a good person. Just as you can’t be generous if you hate being generous.
You’re doing it for the wrong reasons.

Mind you, I’d say it makes a pretty big difference, whether we take the highest good to lie in just possessing [virtues], or using them; a mere disposition, or its exercise. After all, a disposition can be there without aproducing any good effect, e.g. if you’re asleep, or otherwise totally inactive. But when you’re exercising [your virtues] that’s not possible, because you’ll inevitably be doing things, and doing them well {and hence, doing well}.

There’s a big difference in whether we say that possessing virtues is the highest good, or that exercising them is.

For if we say the former, you’d be capable virtuous without even doing anything. You could sleep your whole life and be virtuous.

But instead, if we take the latter to be the case, we must exercise our virtue. We must actually do good.

It’s not the strongest athletes on the practice ground who win the Olympic crowns. It’s the ones who take part in the contests. You have to be in the contest to win. And it’s the same in life: you have to actually do things, and do them right, to win life’s greatest blessings.

If you want to win, you will have to both participate and do well.

Following up:

And life for such people is also pleasurable in itself.

The [tougher the job], the greater the good in doing it well.

So there’s no problem with our claim that you become a fair person by doing things that are fair, and a moderate person by doing things that are moderate.
You certainly have no hope whatsoever of becoming a good person by not doing any of those things. But the fact is, most [young men like you] don’t do them; they shelter themselves in mere theory, fancy themselves ‘philosophers’ and think that’s going to turn them into good men. That’s like patients who listen carefully to their doctors, but don’t actually do anything the doctors tell them to do. Patients aren’t going to make their bodies well by that kind of treatment, and those people aren’t going to improve their souls by that sort of [pure] philosophizing, either.

So a virtue is a ‘middle state’, at least in the sense that it aims at the mid-point.
Also, there are lots of ways of getting it wrong, but only one way of getting it right

It isn’t the mathematical mean, but the mean relative to us.

For example, eating 5 kg is too much for a human in a meal. 0.5 kg is a little. But 2.5 kg, the mean, is still (probably) too much.
It’s relative to us.

Not every kind of action or emotion allows a middle state. In some cases you just name the thing and you’ve automatically implied its badness – things like ‘gloating’, ‘shamelessness’, ‘envy’; or in the case of actions, ‘adultery’, ‘stealing’, ‘murder’. With all of those, and other things like that, it’s implicit in the mere mention of them that they’re bad per se. Never mind too much or too little of them. So there’s never any way of getting it right where they’re concerned

There are actions and emotions with no middle state. You can’t steal too little. There isn’t a middle state of stealing. It’s just bad.

People will always aspire to what they think they’re worthy of. So they hold back from doing honourable things, and from honourable ways of life, if they don’t feel worthy of them. People also hold back from external goods in much the same way.

People will strive for what they think they are worthy of.

What could you be?
What is the story you tell yourself about yourself?

The second-best way [to flourish] is to live a life of exercising the other type of virtue: {your moral goodness}.
All the ways we exercise that are human.
We do things that are fair, for example, or brave, and the other things that express our virtues, to one another, taking care in our exchanges and in [meeting each other’s] needs and in all manner of actions, and in our feelings, to observe what’s fitting for each case. And all those things are clearly tied to our humanity.

This feels more practical than the first way.

For Aristotle, the highest form of rational activity, and thus the highest form of human life, is the contemplative life, which involves the study of philosophical truths.

Best way:
Rational Activity: Since humans are rational beings, flourishing involves engaging in activities that exercise reason. This means not only thinking and making decisions wisely but also understanding and reflecting on the world and our place within it.

What he writes about here is this (2nd best):

Living Virtuously: Aristotle defined virtue as a mean between two extremes of excess and deficiency, related to our passions and actions. For example, courage is a virtue that lies between cowardice and recklessness. To flourish, one must develop and practice these virtues in daily life, making decisions that reflect a balanced, moderate approach to challenges.

So, if we’ve said enough, in broad outlines, about those things, and the virtues, and friendship and love, and pleasure, should we feel that we’ve achieved what we set out to do?
Not really. Because, as we said, our goal in practical matters isn’t just to theorize about all the things {we’re supposed to do}, and know about them. Our real goal is to do them. So the same applies to goodness. Knowing about it isn’t enough. We also have to try to have it and use it. We have to strive, in every way we can, to actually become good people.

Still, the fact remains that if you want to master a technical expertise or theoretical science, for that at least you surely have to make your way to its universal [principles], and get as much knowledge of those as you possibly can.

Grasp the universal fundamentals.