Wittg.–

     But the form of a proposition symbolizes in the following way: Let us consider symbols of the form “xRy”; to these correspond primarily pairs of objects, of which one has the name “x”, the other the name “y”. The x's & y's stand in various relations to each other, among others the relation R holds between some, but not between others. I now determine the sense of “xRy” by laying down: when the facts behave in regard to “xRy” so that the meaning of “x” stands in the relation R to the meaning of “y”, then I say that they [the facts] are “of like sense” [“gleichsinnig”] with the proposition “xRy”; otherwise, “of opposite sense” [“entgegengesetzt”]; I correlate the facts to the symbol “xRy” by thus dividing them into those of like sense & those of opposite sense. To this correlation corresponds the correlation of name & meaning. Both are psychological. Thus I understand the form “xRy” when I know that it discriminates the behaviour of x & y according as these stand in the relation R or not. In this way I extract from all possible relations the relation R, as, by a name, I extract its meaning from among all possible things.