In Steven Universe, there is a character called Sapphire who has the ability to see into the future. For the entirety of the show, it is presented to us as an innate ability which Sapphire can do naturally.
But in one of the final episodes of the show, Sapphire, while supposedly teaching a class on predictions, is seen to be explicitly discussing multiplications of probability to arrive at estimates of the future.
This reflects a larger problem I see with advice: people giving reasons and philosophies for things that can make you happy that are entirely separate from the reasons and philosophies they used themselves to become happy.
The post Life can be better than you think is a great example of this, where the author was severely depressed until they began taking anti-depressants, but a large part of the post is dedicated to explaining his life philosophy of happiness.
But which came first: the life philosophy, or the happiness?
Battling an energy disorder, my own life provides frequent examples of this: whenever I am tired, my thoughts tend towards pessimism and misery, but whenever I have energy they tend towards optimism and joy. It becomes second nature to list out long stretches of philosophical reasoning that justify being happy, but in truth I know the reasoning isn't the reason why I feel happy. I feel happy because I have energy.
Any other reason is a type of fake justification; it may be a way to become happy, but is certainty not what caused me be to be happy in the first place.
Sure, maybe it's possible to become happy just from integrating these long chains of reasoning. This may have been what Naval Ravikant did (or, probably more likely, his low-level interventions — like sleep, working out, and improving relationships — led to better high-level realisations.)
Maybe it's useless and unhelpful to encourage scepticism on people's advice on being happy. Ideas should be discussed on their own first, after all, before you make a single statement about the states of mind that brought about the idea.
But I think, if you're really trying to be happy, what caused the state of mind to bring about any optimistic philosophy is the most important factor, and the thing to try first. Be it better sleep, antidepressants if you need them, better friends, or more meaningful work.
Whatever brings about the states of mind that bring about the philosophy is what you really want, not necessarily the philosophy itself.