 Certainly, different kinds of laws can be distinguished from each other: for example, chemical, biological or sociological laws; however, it can not be said of a prediction of a concrete individual process that it depend on one definite kind of law only. For example, whether a forest will burn down at a certain location on earth depends as much on the weather as on whether human intervention takes place or not. This intervention, however, can only be predicted if one knows the laws of human behaviour. That is, under certain circumstances, it must be possible to connect all kinds of laws with each other. Therefore all laws, whether chemical, climatological or sociological, must be conceived as parts of a system, namely of unified science. (Neurath 1931/1983, 59, orig. itals.)