Equipped with his five senses, man explores the universe around him and calls the adventure Science.
There we measure shadows, and we search among ghostly errors of measurement for landmarks that are scarcely more substantial.
Observations always involve theory.
Past time is finite, future time is infinite.
The history of astronomy is a history of receding horizons.
The outstanding feature, however, is the possibility that the velocity-distance relation may represent the de Sitter effect, and hence that numerical data may be introduced into discussions of the general curvature of space.