Hi, I'm Julien.

I'm a French embedded systems engineer that follows the Greek ideal. Something that goes: "Mens sana in corpore sano."

The only way to get the most out of a system is to understand how it works. We spend years learning a job and getting a place in this society. For what's left, you have to figure it out by yourself. We don't know how to handle power, how to handle emotions, how to be healthy, how to live happily, etc.

This site is my boarding journal. I want to get the most out of this system called life and share my journey with you. Here you'll find actionable lessons to build a strong personal philosophy.

My favorite topics are neuroscience, psychology, history, biology, philosophy, and interpersonal relationships. It is thus through their prisms that I decipher this world to conquer it better.

Why You Will like My Site

1. I share what works. Just because I read it somewhere or everyone tells me it's the best thing ever doesn't mean I'll write about it. It's when I have felt a benefit that I take the step.

2. Each post comes from hours of writing and re-writing. I believe those wonderful ideas can't spread if they aren't well distributed. More than a process, writing well is a subject I'm actively working on to publish the best possible content.

3. I draw my posts' illustrations. My goal is to catch what comes to my mind and reproduce it on your screen. I want them to be simple but deliver the message clearly.

Do you like it? Add my website to your RSS feeds. You can also sign up for my Newsletter.


The easiest way to contact me is on Twitter (@mentalcodex). You can also send me an email to say hello (julien.fichet17@gmail.com), I'll be happy to answer you.


Interests go back and forth as the content of this section. Come from time to time to see what I'm on these days.


I love to sleep. It was the book Why We Sleep that opened my eyes to this essential pillar of life. For me, a day of sleep deprivation is a day lost, so I've developed many habits to improve it over time. 


I have an entire section that lists my best reads. I also love blog posts and Twitter threads. My favorite online writers are; Julian Shapiro, Derek Sivers, James Clear, Farnam Street, and Paul Graham.

Food Supplement

I take 1080mg of EPA and 720mg DHA daily (in the form of Omega-3 capsules) and 100mcg of Vitamin D3. Before sleep, I also take 300mg of Magnesium Bisglycinate and 22mg of Zinc Picolinate.


I listen to podcasts while I walk or as I'm on the road. My favorite one is the Huberman Lab. I also love the Time Ferris Show, Naval, The Knowledge Project, and The Joe Rogan Experience. I use Snipd for listening and taking notes.


I exercise 4 times a week for 1 hour. I practice kettlebell cross-training, alternating between upper-body and lower-body exercises.