The Indirect Test
The point of departure for the indirect attack is the scale of distance as determined from apparent luminosities. There are evidently two possible scales, depending upon whether or not the nebulae are receding. The distinction is not merely a difference in the unit; the ratios of the distances on the two scales do not remain constant. Consequently, the wrong scale may lead to peculiarities or inconsistencies in the map of the observable region, which might be recognized, or, at least, suspected. The project of mapping the observable region in detail cannot be carried out, but it is possible to examine precise formulations of the general characteristics of the region. Actually, the investigation reduces to a study of the laws of red-shifts and the laws of nebular distribution as derived from the alternate scales of distance.