To laugh often and much; To win the respect of intelligent people and the affection of children; To earn the appreciation of honest critics and endure the betrayal of false friends; To appreciate beauty, to find the best in others; To leave the world a bit better, whether by a healthy child, a garden patch, or a redeemed social condition; To know even one life has breathed easier because you have lived. This is to have succeeded. - RALPH WALDO EMERSON

“You are never dedicated to something you have complete confidence in. No one is fanatically shouting that the sun is going to rise tomorrow. They know it's going to rise tomorrow. When people are fanatically dedicated to political or religious faiths or any other kinds of dogmas or goals, it's always because these dogmas or goals are in doubt.” 
― Robert M. Pirsig

“In a car you're always in a compartment, and because you're used to it you don't realize that through that car window everything you see is just more TV. You're a passive observer and it is all moving by you boringly in a frame. 
On a cycle the frame is gone. You're completely in contact with it all. You're in the scene, not just watching it anymore, and the sense of presence is overwhelming.” 
― Robert M. Pirsig

“The real purpose of the scientific method is to make sure nature hasn’t misled you into thinking you know something you actually don’t know.”
― Robert M. Pirsig

“The past exists only in our memories, the future only in our plans. The present is our only reality. The tree that you are aware of intellectually, because of that small time lag, is always in the past and therefore is always unreal. Any intellectually conceived object is always in the past and therefore unreal. Reality is always the moment of vision before the intellectualization takes place. There is no other reality.” 
― Robert Pirsig

On "The Elephant in the brain: Hidden Motives in Everyday Life" by Robin Hanson and Kevin Simler

• 1.) My general opinion:

While the book started out with many ideas that are by now both obvious and boring to me, they made a very successful turn in delivering a bunch of new ideas and useful insights soon after. Therefore I can conclude that I very much would recommend this book and enjoyed reading it a lot.

• 2.) I have one concrete criticism or piece of input on “Puzzle 3: The Criterion of Relevance"

Hanson and Simler write:
"According to the reciprocal-exchange theory, conversations should be free to bounce around willy-nilly, as speakers take turns sharing new, unrelated information with each other. [...] Either listener might ask follow-up questions, of course. But as soon as their curiosity had been satisfied, they might be expected to turn around and share some new information of their own, regardless of whether it pertained to the previous discussion.
But this is not what human conversation looks like. Instead, we find that speakers are tightly constrained by the criterion of relevance. In general, whatever we say needs to relate to the topic or task at hand. Conversations can meander, of course, but the ideal is to meander gracefully. Speakers who change the topic too frequently or too abruptly are considered rude, even if[…]”
“And so it is with conversation. Participants evaluate each other not just as trading partners, but also as potential allies. Speakers are eager to impress listeners by saying new and useful things, but the facts themselves can be secondary. Instead, it’s more important for speakers to demonstrate that they have abilities that are attractive in an ally. In other words, speakers are eager to show off their backpacks.”
“If we return to the backpack analogy, we can see why relevance is so important. If you’re interested primarily in trading, you might ask, “What do you have in your backpack that could be useful to me?” And if your partner produces a tool that you’ve never seen, you’ll be grateful to have it (and you’ll try to return the favor). But anyone can produce a curiosity or two. The real test is whether your ally can consistently produce tools that are both new to you and relevant to the situations you face. [...] His backpack, you infer, must be chock-full of useful stuff. And while you could—and will—continue to engage him[…]”
I think:
the "criterion of relevance" as a constraint to signalling in conversations is not a proxy (signal) for the "size of the backpack" but instead shows a very concrete and rare skill: the ability to transfer and use knowledge one has to someone's benefit. I don't care about the number of tools someone has if he lacks the ability to use the appropriate tool in a given situation. The usefulness of someone's backpack is the product of the size of the backpack and the ability of the person to hand me and use the needed tool in a given situation. To produce relevant content is not just a signal, but a skill. I think Hanson and Simler took the signaling hypothesis too far in this case.

Look at my amazing abs!* And now that I have your attention, let me tell you why you should start to lift weights. Heavy ones. Especially as a women. Or at least why or how well it works for me.

Time travel
If I could go back ten years in time and transport one idea to my former self, I would have a hard time to decide what words to pass through. What would have the biggest impact on my well-being, life satisfaction or personal development if I had known it earlier? First, a lot of abstract concepts come to mind: “rationality” or “philosophy of science” or “effective altruism”. They changed my perception of the world drastically. But in terms of happiness and self mastery I definitely would say “quit cardio, start lifting heavy” or even simpler “fall in love with getting strong”. (Thanks to Valentin Tambosi for the phrase)

Before: Losing weight
For years I was running, cycling, worrying about calories, massively reducing my food intake (alternating with extreme cravings) and was going through periods of quick weight loss and gain. Not only didn’t I reach my goals long-term: it also was unhealthy, took big parts of my attention and time as well as caused self-doubt and suffering. Because despite following harsh plans I was not able to realise my goals. Neither in terms of appearance, nor in terms of subjective fitness and physical well-being. In theory it is so easy: Lose weight by burning more calories than you eat. But, well, it wasn’t.

Heuristic for success: strength
After a year of more or less constant working out with (for me) heavy weights and being happy with the results like never before, I can summarise what made the difference for me:

• Weight loss isn’t the goal that works for me, getting strong is.
• Body weight is not the best heuristic to measure fitness successes, weight lifted (increasing objective strength!) is.

Why?
The attempt to make the answer short has two parts, a mental and a physical one:
1. Mentally to focus on strength changes my mindset rigorously.
When I define weight loss and reducing body weight as my goal, the thoughts that will pop up on this path focus on how to reduce and burn body fat and therefore prioritise reducing calories and food intake. The framing is more negative, it focuses on what I want to get rid of instead of what I want to reach.
Strength mentally puts muscle growth in the center. This implies to healthily nourish the body to allow the muscles to grow and it is more positive. Even if there are still things you would want to change or get rid of, there is something getting bigger and better that you can be proud of. Also it is more long-term, because muscles only grow slowly with constant stimulus, but also need breaks and the right circumstances like nutrition and sleep. The goal of getting strong does not tempt you to do extreme things (like starting a crash diet), because it is more apparent, that it will not work and takes time.
2. Physically a focus on strength also makes sense.
Gaining muscle mass will (more or less independent from body weight) make you look slimmer (the same kg of muscles have way less volume than body fat) and on a daily basis add to your basic metabolic rate (calories burned). Without (at least in my case!) increasing hunger or leading to cravings.
Instrumental goals

• Regularly use free weight compound exercises and learn the correct execution. (A popular and good guide is Stronglift 5x5. Consider getting a coach for starting or find someone with experience to join you in the gym.)
• Prioritise correct execution, weight lifted should be your second priority, though. Regularly increase the weights. (For me this also meant to overcome mental challenges, like assuming I never could e.g. squat over 70kg and therefore not trying for months. In general, while valuing safety, don’t be afraid of lifting heavy. Especially as a woman: You will not get bulky unless you take steroids.)
• Take enough breaks between workouts which train the same muscle groups. Sleep enough.
• Eat enough protein and as a rough heuristic also eat fruits and vegetables and other nourishing things that are low in calories. Mostly focus on what your body needs to get strong, eat enough in general.
• While my story might inspire you, always seek out professionals to answer your questions and to learn from.

Too late
I can not tell this myself ten years ago, but I share this out of hope that I will spare or shorten someone else the long process of learning these lessons!