  Now, insofar as it is not a law that polar bears live at the North pole, even though they happen to live there, a compass will fail to carry information about where polar bears happen to live in spite of the fact that it does carry information about the North pole. If so, then reports of what a compass indicates exhibit one of Chisholm’s features of intensionality, namely coextensive terms are not freely substitutable salva veritate in such reports. By contrast, if it is law that variations of temperature covary with variations in atmospheric pressure, then by virtue of indicating the temperature, the height of the column of mercury in a thermometer will also indicate atmospheric pressure. If there is a law relating current flow to voltage differences, then by indicating the former, a galvanometer will indicate the latter. One can, however, believe and even know that there is a current flow between two points without believing, let alone knowing, that there is a voltage difference between the two points, if one fails to know that it is a law that if there is flow of electric current between two points, then there is a voltage difference between these two points (see Jacob 1997 for discussion).