Thus, in general, in the first instance, the direction of interest in empirical fact will be canalised by the logical structure of the theoretical system.
In so far as such a theory is empirically correct it will also tell us what empirical facts it should be possible to observe in a given set of circumstances.
Now obviously the propositions of the system have reference to matters of empirical fact; if they did not, they could have no claim to be called scientific.
That is, a system starts with a group of interrelated propositions which involve reference to empirical observations within the logical framework of the propositions in question.