RE: About selection on propierties based on itself (that is, propierties as selectors)

Then why suppose that the human have failed instead of not?. I mean: why is
more logical this estructure of overriding by precedence than by , let's
say, propierties as selectors?(reckognizing that in this way it loses the
meaning of shorthand propierty)

In the example it would be:

whatever {margin-left:2em;margin:2pt} <=> whatever
{margin-left:2em;margin-top:2pt;margin-right:2pt;margin-bottom:2pt}


> Margin is a shorthand property, it sets four properties at once. The
> above actually means:
>
>     whatever {margin-left:2em}
>     whatever {margin-top:2pt}
>     whatever {margin-right:2pt}
>     whatever {margin-bottom:2pt}
>     whatever {margin-left:2pt}
>
> So the first 'margin-left' is lost because the last one takes
> precedence.