There are
excellent reasons why
Leibniz would have left some works unpublished. For a start the same reasons that many authors have, not each work is
for publication.
Ideas,
musings,
personal quests for knowledge while deemed invaluable after a person is dead are always open for
question and fraught with
worry when alive as they burn in the crucible of
peer review.
'Publish and Be Damned' is not an idle proverb.
And he would have been. Authority and Freedom were closely associated. God gave us our freedom, and He himself was the all important figure in Christianity, to imply that he was somehow *limited* by his Goodness would of course be seen as heretical, and even blasphemous, and would have gained what? A few imaginary points in the minds of princes/gorillas who would have smashed him to bits for disturbing their blood-paid social order? A wise man lives long enough to think and to be wise is not always to be strong.
There is another point. More philosophical, if you will. The different kinds of impossibility (due to character or due to innate Form-al definition) are indistinguishable when approached from a practical standpoint. Do we care if Caesar was 'free' to cross the Rubicon or not? We do because he did. What of the right angle? Labelling aside a 45 degree angle would be of little use in the place of a 90 degree angle, and hence unless we were dealing with a separate geometry the notion is the way it is because it affects us in a very particular way.
Leibniz, God bless him, was a practical man. He understood that there is little we can do about the Forms which govern our existence.
However we know that when we begin to apply our familiar concepts of freedom to God they lose traction.
A person is 'free' so long as they can choose between a variety of ways to solve their current problems and select possible future problems. For God (or Allah, if you're Muslim) there are no such problems. So the capacity for freedom we would assign a person doesn't hold for a Divine Being. Simply because I don't think we can fully understand those who are more free than us.
Given all this, I think he did rather well.