Bertrand's position on happiness reads straightforwardly, but it actually takes quite some introspection to formulate it as such.

I did not really enjoy reading this book; experienced it as a slog. The texts feel hard to get through, with lots of fluff for what ultimately feels like a straightforward idea or concept. However, those ideas are really fundamental and helpful to fully grasp. Though the texts are about a hundred years old, which I subjectively experience as quite a long time, many of the struggles seem to hold up significantly well in this day and age. Then again, texts such as Aurelius's Meditations are a factor of ten times older but those also hold up pretty well. This might be the survivorship bias's influence. Anyway, the book is available online at the Internet Archive.

Bertrand splits up his book in two parts: 1) causes of unhappiness, and 2) causes of happiness.

Unhappiness

The aspects of unhappiness Bertrand discusses are the following.

I won't be giving a comprehensive survey of his extended opinion on all of them. Let me just reference some highlights I made along the way.

I believe this unhappiness to be very largely due to mistaken views of the world, mistaken ethics, mistaken habits of life, leading to destruction of that natural zest and appetite for possible things upon which all happiness, whether of men or animals, ultimately depends.

A man may feel so completely thwarted that he seeks no form of satisfaction, ut only distraction and oblivion. He then becomes a devotee of "pleasure." That is to say, he seeks to make life bearable by becoming less alive.

Men who are unhappy, like men who sleep badly, are always proud of the fact.

If I lived forever the joys of life would inevitably in the end lose their savor. As it is, they remain perennially fresh.

From Competition

There are two motives for reading a book: one, that you enjoy it; the other, that you can boast about it.

From Fatigue

A great many worries can be diminished by realizing the unimportance of the matter which is causing the anxiety.

From Fear of public opinion

This has been one of the advantages of aristocracy, since where status depended upon birth behavior was allowed to be erratic.

Happiness

The aspects of happiness Bertrand discusses are as follows.

These are a mix of qualities that may motivate happiness, and discussions on what happiness means in certain personal situations. I will again just jot down some quotes I highlighted.

From Affection

[...] general self-confidence towards life comes more than anything else from being accustomed to receive as much of the right sort of affection as one has need for.

The world is a higgledy-piggledy place, containing things pleasant and things unpleasant in haphazard sequence.

In the best kind of affection a man hopes for a new happiness rather than for escape from an old unhappiness.

Caution is enjoined both in the name of morality and in the name of worldly wisdom, with the result that generosity and adventurousness are discouraged where the affections are concerned. All this tends to produce timidity and anger against mankind, since many people miss throughout life what is really a fundamental need and to nine out of ten an indispensable condition of a happy and expansive attitude towards the world.

Of all forms of caution, caution in love is perhaps most fatal to true happiness.

From The family

[...] how can all these exquisite and ingenious weapons of destruction function adequately unless there are sufficient populations left for them to destroy?

To be happy in this world, especially when youth is past, it is necessary to feel oneself not merely an isolated individual whose day will soon be over, but part of the stream of life flowing on from the first germ to the remote and unknown future.

[...] nothing causes so much worry in a child's mind as lack of certainty and self-confidence on the part of an adult.

[...] the mother, if she is not unusally saintly, will expect from her child compensations exceeding those she has a right to expect. The mother who is conventionally called self-sacrificing is, in a great majority of caess, exceptionally selfish towards her children, for important as parenthood is as an element of life, it is not satisfying if it is treated as the whole of life, and the unsatisfied parent is likely to be an emotionally grasping parent.

From Work

Two chief elements make work interesting: first, the exercise of skill, and second, construction.

[...] the rest, for the sake of a livelihood, prostitute their skill to purposes which they believe to be harmful.

Without self-respect genuine happiness is scarcely possible. And the man who is ashamed of his work can hardly achieve self-respect.

The habit of viewing life as a whole is an essential part both of wisdom and of true morality [...]

Consistent purpose is not enough to make life happy, but it is an almost indispensable condition of a happy life.

From Impersonal interests

It is one of the defects of modern higher education that it has become too much a training in the acquisition of certain kinds of skill, and too little an enlargement of the mind and heart by an impartial survey of the world.

From Effort and resignation

Half the useful work in the world consists of combating the harmful work.