1.   A scientific theory, not just a rhetorical one.

2.   Appeal to ecclesiastical censure as a way of explaining the misfortunes of scientific theories is a card that can be overplayed.

3.   Fletcher turned his trick into a whole scientific theory.

4.   For scientific theories to be considered tenable, they must survive refutation.

5.   In itself this does not seem to me to point the way towards any helpful scientific theory of mind.

6.   In still another respect we hope to contribute to the development of a scientific theory of democracy.

7.   It is difficult to establish which of the two scientific theories could hold sway.

8.   Many scientific theories are never proved and slip into obscurity.

9.   No doubt that story contained many scientific theories which she had had to omit from her tale, being unable to comprehend them.

10.   That does not stop it being a good scientific theory.