The main concern of the study is with the outline of a theoretical system. Its minor variations from writer to writer are not a matter of concern to this analysis. ↗
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. ↗
A theoretical system does not merely state facts which have been observed and that logically deducible relations to other facts which have also been observed. ↗
Mental illness, of course, is not literally a 'thing' - or physical object - and hence it can 'exist' only in the same sort of way in which other theoretical concepts exist. ↗
This success led my theoretical group to the chemical reactivity theory, extending more and more widely the range of compound and reactions that were discussed. ↗
About 1960, it became clear that it was best for me to bring the experimental part of my research program to a close - there was too much to do on the theoretical aspects - and I began the process of winding down the experiments. ↗