my upshot here is avoid the whole situation by not using any of it if possible
there are many reason why you may never "get justice" and should "try another way that doesn't involve EPS or maybe even PS either
I don't have time to test this but I do know basic postscript programming.
As the person above said: save a simple Mathematica plot (it has text) then hit Ctrl-Shift-e you'll see the postscript (eps) code. (it works, your other software is not working)
The plot will import and export (there is a few minor bugs with line width for tables in some cases).
The EPS is both Adobe (paid use non-free) and Mathematica postscript code, in the postscript programming language. PDF is similar but newer version and is (partly) compressed (you can't see all the code without finding the right de-compression).
The Mathematica postscript in each .ps or .eps does two things:
(1) it provides the postscript programming for using Mathematica fonts (for loading them, naming them, scaling them - ie for radical verticuland width, printing them at the right width). you have to have those fonts installed on the system or you won't see them in GhostScript. they are copyright wolfram your not allowed to "share them" (if you bought mathematica there are instructions for installing fonts for ghostscript to make use of for the purpose of printing)
(2) it provides basic functions for doing plot lines and such (in the ps programming language, with frames of total width and units - which is a new bug sometimes the total width is wrong so the line width gets multiplied wrong). i'm unsure when and if what ps functions go automatically in every .eps - but there will be some in there. typical ps functions do things like check plot range and plot scale and generate tick marks for axis based on scale. for example this would be in an EPS:
(0.5)Tj
(is some text)
Tj is a wolfram function that ads postscript code as to the font and placement of the text
actually i see wolfram has "lifted" gpl'd cairo borrows from linux libs (that's probably both un-necessary and probably why it's has new bugs. but i'd have to check if adobe has released it's own cairo. cairo was originally a rewrite of postscript graphics for X that "stole postscript" and extended it's vector abilities which in turn could be used on the X desktop with X.org - but many no longer support x.org because of many many reasons)
