The rule remains: _Consistent analysis of the same output with reference to basic topics over a sustained period will inevitably reveal the propaganda intention of the source._ (It must be pointed out that the expert analyst still is needed to select topics and to confirm interpretations.) To make a first guess as to whether the intended effect is being achieved or not, the analyst uses himself as a propaganda guinea pig. What does he think of the issues? What might he have thought otherwise? What would he think if he were a little less intelligent, a little more uncritical, than he is? And to complete the analysis, the analyst must go out to the audience that receives the materials and find out what effect the propaganda has had by asking them about it (see interrogation, page 145). =Printed Materials.= The most readily available sources of propaganda are not printed ones. Especially in time of hostilities, it may not be easy to subscribe to enemy materials by the process of sending an international postal money order. Delays involved in transmitting the printed materials may make them useless for spot analysis, and valuable only for long-range basic studies of morale. The propagandist who is being analyzed may oblige by reading large numbers of editorials on the radio. (During the last war, officers and citizens occasionally exploded with alarm when Radio Tokyo quoted a _Life_ or New York _Times_ editorial several hours after it appeared. They naturally supposed that the Japanese had a secret short-wave transmitter running from New York City direct to Tokyo, and overlooked the fact that the OWI may have quoted long excerpts in slow Morse code on its trans-Pacific beam to China. The Japanese had picked it up, used subquotes, and beamed it back.) Printed matter goes on the air in any major news operation. It is only a matter of time before telephoto facilities develop in line with the experimental New York _Times_ edition printed in San Francisco during the United Nations organizational conference. This was sent, all in one piece, by wirephoto to Frisco and reprinted. The delay between the two editions was merely a matter of minutes. In the future, wireless telephoto may reduce this to seconds, so that all belligerents can simply tune in on each other's major newspapers. =Radio.= For the present radio remains the biggest source of propaganda intake. Radio is convenient. It can be picked up illegitimately without too much fear of detection. For the cost per person reached, it is certainly the cheapest way of getting material to millions of people promptly. It lends itself to monitoring, and even standard (long) wavelengths can be picked up from surprisingly great distances.