In that regard, a deliberately quiet exchange between colleagues on a matter important enough to discuss in the library is usually permitted in person. But for the rules necessary to address wholly inappropriate types of conversations (and volumes) of obnoxious cell phone users in restaurants and libraries, such harsh rules would be unnecessary.
The reason cell phones must be banned, absolutely, from restaurants, libraries, and even gyms is simply because people whose cell phone habits are completely obnoxious ruin it for the rest of us. People who use cell phones appropriately tend to share certain traits: (1) they speak in the lowest possible volume necessary, (2) they purposely turn away from others and shield their conversations with their bodies as much as possible, (3) they cover their other ear, (4) they understand the difference between situations where “necessary” conversations are acceptable but purely social conversations inadvisable or offensive, based on social context, and (5) they understand that all the same principles apply to the ringing of a cell phone as well.
Conversely, people whose cell phone habits are obnoxious share much different traits: (1) they speak in volumes that are quite a bit louder than would be appropriate if they were conducting a face-to-face conversation while in public, (2) they turn to face the greatest number of people, (3) they face straight ahead or slightly upward, (4) they hold their elbows as high as their heads so that their arms and body approximate the cone of a megaphone, (5) they have absolutely no sense at all as far as distinguishing what types of conversations and volumes of conversation are appropriate or inappropriate depending on the environment, and (6) they have never considered that a vibrate only setting or the shortest beep possible (answered on the first ring) may be more appropriate in certain settings than 30 seconds of the worst music in the.