Solution to what? It is crucial to get the definition of the problem correct before considering possible soluions thereto. For instance, suppose we wish to solve the problem of human world hunger. One possible solution is to nuke all humanity into oblivion. Clearly this is ridiculous. But why? Doesn't it solve the problem perfectly? Yes, it does. The reason it is ridiculous is because while the solution solves the stated problem, the stated problem is not the actual problem we have in mind. There are implicit conditions on the possible solutions that are inherent to the problem, which any solution must accomodate. Sometimes it is difficult to figure out all these implicit conditions in advance. So I think firstly you need to describe the problem that the "one state solution" is supposed to solve. Then you need to describe what this "one state solution" means. For instance, how about the following "one state solution": Israel (67 borders) becomes the 51st state of the USA. Here we took two countries ("states"): the US and Israel, and merged then into one. A one-state solution.

One of the techniques to hone in on what the problem really is, whose solution you're after, is to consider many possible solutions to it. For instance, suppose the problem we wish to solve is the elimination of Israel's violation of international law. One possible solution to this problem is to change international law in such a way that Israel will not be found in violation of it. If you think this is funny, it is important to ask yourself: why? Why can't this be a valid solution to the problem? Once you have an answer to this, you need to adjust the problem statement correspondingly. For instance, you might say that changing international law in this manner is unlikely due to political reasons. So the problem now transforms into: "Eliminate Israel's violation of international law within the confines of what I deem to be politically possible at the present time, from the aspect of international politics." Or, alternatively, you might say that even if such a change to international law were a real possibility, you would reject it, because it does not respect the right of the Palestinian people for self-determination, which is a right that transcends international law. In this case, the problem becomes: "Eliminate Israel's violation of International law, while observing the Palestinian's right to self determination."