As pretty and bold as the philosophy sounds, I think it lacks quite a bit of foresight, given that once men become "free", they historically begin taking other freedoms away, in one form or another; most people advocating world peace or revolution in the mask of freedom fail to realize that they themselves will be the successors of the throne of oppression.
The definition of freedom is sadly ambiguous. Diderot attempts to define freedom as freedom from oppressive monarchies and theocracies. But no amount of purging of such things can make the world complete for humanity in the sense of freedom we think of. Freedom from religious and governmental oppression is free in some aspects for some people, perhaps, but not for all, which calls into play the ultimate difficulty of freedom vs. equality.