 In the empirical case, the distinction seems to be between the physical properties of an object and the sensory qualities it presents to differently situated human observers. This requires distinguishing between what is “valid for every human sense in general” and what “pertains to [objects] only contingently because [of] … a particular situation or organization of this or that sense” (A45/B62). The distinction seems to be that some properties of objects are represented in experience just in virtue of the a priori forms of experience, and thus have inter-subjective validity for all cognitive subjects, while some properties depend upon the particular constitution of our sense organs (cf. A226/B273). The “empirical thing in itself” is the empirical object qua bearer of the former set of properties, while the “empirical appearance” is the empirical object qua bearer of all of its properties, including the latter. For instance, the empirical “rainbow in itself” is a collection of water droplets with particular sizes and shapes and spatial relations, while the empirical “rainbow appearance” is the colorful band we see in the  sky.[5]