Why does thermodynamics laws look like a tautology ?
1st law of thermodynamics :
There is something that will always be the same.
2nd law of thermodynamics :
Everything else always changes and never will be what it was before.
It's very important to understand the rule and the implications. It's self-consistent. They are axiomatic, so if you can come up with a better system that and demonstrate it you can beat it. But until then they're laws.
My misquotation was on purpose.
in the same thread of thoughts : if there was a system without the first law, anything could appear as if by magic !
...that is, until the 1st law appears.
It sounds like you're confused on what a natural law is. They do not prescribe the behavior of a system, they describe it.
The first law is a law because our observations state that all systems obey it, not the other way around.
What you're saying is "If there was a system that behaves fundamentally differently than every system yet observed, then it would not follow the laws of thermodynamics." Which is kind of the point.
Probably because wherever you got those definitions of the laws of thermodynamics is just wrong. If I assume it's your own paraphrasing of the laws then your understanding of what the laws mean is incredibly flawed
The 1st law discusses energy. The total energy contained within a system totally isolated from others will not gain or lose total energy, but it can be transferred between places or change forms.
The 2nd law discusses entropy. The total net entropy of systems in natural interactions always increases. This isn't in contradiction to the 1st law, because the same net energy is there, but after any thermodynamic process, that energy just takes on a form that is more entropic than before.
These laws haven't been "ordained" by anyone, just scientists' best guesses for how the world works using our observations.
Setting aside for a moment your (purposeful?) mistaken rendition of 2 of the 4 Laws...
I like to characterize them this way:
0th Law - Everyone is playing this game (definition)
1st Law - You can't win
2nd Law - You can't break even
3rd Law - You can't quit playing
These aren't rules some entity has given us. As best we can determine, these just describe the way the universe works as regards energy. But instead of everyone having to discover them over and over or in every new proposed application, our Very Smart People have discovered them and recorded them.
I don't see anything in there that's along the lines of "this is true because it's true." The laws of thermo aren't provable except by observation, because they are the first principles. If there were first principles from which we could derive the laws, those would be the laws.
That's not to say they don't exist, because they might. We just haven't found them yet, if they do. I have gone through the mathematical foundation but I'm on the fence as to whether that counts as a "first principle" since it has a sort of "chicken & egg" problem.