Just about everyboy now a day is familiar with the Star Trek Prime Directive, the law that prevent star fleet captain from interfering with the develloppement of non warp capable species not to destroy/pollute them. Apparently the Ancient, the Tollan and the Nox in the Stargate universe have similliar law (even if the Asgard from the same universe apparently do not.. except for weapons) with various reason. Now such a law probably are a good idea and for the Tollan at least come from experience of giving technology to a less advanced race and suffering dramatic repercussion for it. But they suffer from a basic problem in my opinion, how do you define a primitive society?
You go with the Star Trek approch and put a single defining technology as a base for your technological sharing? You go with the Ancient and simply wait for everyone to have evolved pass the need for body? The Tollan way seems more logical, if they posses technology you do not and you posses some they do not you can share as you obviously are on a similar level. Maybe you only share with species having a simillar outlook in life, like the Nox? Each one of those approch have problem i guess, the Star Trek one relies on technology not cultural advance meaning that you could technically give nukes to a cultures that would fire them at each other before realising their potential for destruction. The Ancient non inteference policy would probably work.. if they had not littered the universe with relics and weapon not to mention entire city full of their knowledge. The Tollan well if you watched Stargate you know how their view ends... and finally the Nox well I can't find much fault with the Nox approch except that the odd of you finding another compatibly species is very low.
Their is finally the problem of the simple existance of that old technology, suppose for some reason the primitive being simply learned of the existance of that technology, the knowledge might be enough to drive them toward seeking that technology. Afterall if species X can do it, then it is possible to do it and we would be crazy not to try.
Personaly if I was writing the laws for space exploration I would include an non interference law, but it would be slightly more complex then the prime directive. The law would state absolutly no contact unless the species has had self-destruction capability for at least 10 of it's generations or at least one colony in another star system. For exemple, for humanity this fictional advanced species wouldn't be allowed to contact us until 2245 (edit: 2145 as stormcrow pointed out...), i.e 200 years after the building of the first nuclear weapon. The second part stand because you will sooner or latter meet the species if it is capable of traveling the stars and the out system colony makes instant destruction very difficult. I do not tie the law with nuclear weapon because i can easilly imagine a species building biological weapon with the same potential or a more advanced species could be able to drop asteroids on itself. This criterium in my mind prove that the species is technically advanced and the it as at least advanced enought socially not to destroy itself at the first opportunity.
I think this would be a good space exploration law no?