[koonsolo]

I never heard of "first principles" until Elon Musk used it. (Not a native English speaker) Now I see it everywhere.

Must be the new overhyped term. "We start from first principles, just like Elon Musk".

After looking at Google trends, I might be wrong, so nevermind ;) https://trends.google.com/trends/explore?date=all&q=First%20...

[wenc]

First-principles is a physics/math way of thinking, and is common parlance in the mathematical modeling world.

When we say a model is a first-principles model, it means it is derived through fundamental equations like conservation of mass/energy, and other known relationships. This is in contrast to a data-driven model, where the underlying phenomena are not explicitly modeled -- instead the model is created by fitting to data.

Elon Musk became associated with it because he applied this form of thinking to business problems, i.e. by establishing the "fundamental equations" (as it were), questioning some basic assumptions and coming up with conclusions that are necessarily true but that no one else has arrived at.

Data-driven models (or the human equivalent: reasoning by analogy) are convenient to build and work well in the space the data has been collected in (~interpolation). However, they do not extrapolate well -- you cannot be sure they will work outside of the space of training data that the model has seen.

First-principles models (or the human equivalent: reasoning by principles) are generally more difficult to build and test (I worked on first-principles physics models for a decade -- they are a pain), but because they are built on a structure of chained principles/truths, they often extrapolate well even to areas where data has not been collected.

This is why if you want to improve efficiency and operations in known spaces, you use data-driven models (fast to build and deploy, accurately captures known behavior).

But for doing design and discovery (doing new things that have never been done before), first-principles models/thinking will carry you much farther.

[eandre]

That's the Baader-Meinhof phenomenon talking [1] :)

[1] https://science.howstuffworks.com/life/inside-the-mind/human...

[siddboots]

It's a relatively common idiom here in Australia. It gets used quite a bit in STEM education, i.e. "prove such-and-such from first principles", but is also pretty common more colloquially.

According to your link, it is also used a bit in South Africa (where Elon grew up), but less common in the US. Rather than being a new and overhyped term, perhaps it is a case of Elon using a term that is quite everyday to him, without realizing it is less familiar to the audience.

[decentralised]

FWIW, the latin form "ab initio" is not uncommon either (in Europe at least).

https://en.wikipedia.org/wiki/Ab_initio

[chestervonwinch]

It often occurs that technical jargon is swiped to be used as business speak by business leaders with technical backgrounds. For example I often hear “orthogonal” when “independent” is usually more appropriate.

[empath75]

Aristotle used the term, and it’s probably older than him.

[marcosdumay]

It's all over the place in physics and chemistry, and as a consequence on the engineering areas that are based on those (AKA, nearly all of them).

It is rarer to see it in CS, but it's more because CS used to deal with very simple theories up to recently than because of some fashion. As CS theories start to construct up from the earlier ones, it's appearing more.

[KineticLensman]

UK here - I remember it back in college thirty+ years ago as in "build X from first principles", which could mean (e.g.) implement an algorithm without out using library calls.

[joshspankit]

Possibly the Baader-Meinhof Phenomenon

[itronitron]

It's a favorite term used by people that identify as 'thought leaders'