The form of a proposition has meaning in the following way. Consider a symbol xRy. To symbols of this form correspond couples of things whose names are respectively x and y. The things x/y stand to one another in all sorts of relations, amongst others some stand in the relatio[j|n] of R, and some not; just as I single out a particular thing by a particular name I single out all behaviours of the points x and y the one between with respect to the relation R. of the other. I say that if an x stands in the relation of R to a y the sign x of R y is to be called true to the fact and otherwise false. This is a definition of sense.