ABSTRACT
The precarious rope bridge between the world of the rabbits and our own familiar world represents the uncertainty with which scientific hypotheses can be translated into statements about what-ought-to-be-observed-in-what-circumstances in reality. Bridgman s argument is quite simply that to be meaningful a variable must be defined in terms of the measurement operations that would be involved in detecting it in reality. The Map of the Campaigns for the Bridges can of course he simplified for our purposes. In bald form it looks like the design on the tables in the rabbits' refreshment marquee. It is what in the rabbity world is usually called a typology, a device for expressing a number of distinct but simultaneous classificatory distinctions. Oil the other bridge, marked 'Theory Testing', an equally nasty fracas is in progress, this time between the positivists and the idealists. Within the positivist army the real extremists are the operationists.
