The purpose of Biorhythm is to predict a physical, emotional and intellectual pattern that indicates your up and downs for any period of time. Biorhythm can show which future days will be good or bad for you. These predictions are based on scientific studies that show a physical cycle occurs every 23 days, an emotional cycle every 28 days and an intellectual cycle every 33 days. When the graph is to the right of the centerline, the Biorhythm is 'High', with energy to spare. For example, on a physical High, we tend to be energetic, strong, and full of vitality. On an emotional high, we're apt to be creative, artistic, aware, and cheerfull. On an intellectual high, we are able to think quickly and solve complex problems easily. When the curve is to the left of the centerline, the Biorhythm is said to be 'Low', or in a recharging state. Physically, we tend to tire more quickly, feel dragged out and succumb to colds and other illness more readily. Emotionally, we are apt to feel moody, irritable, or depressed. Intellectually, we may find it difficult to concentrate or remember, and may get easily distracted, and be more likely to use poor judgment. The day that the curve crosses the centerline is called a 'Critical' day. On this day your system seems to be in a flux or transition, and is therefore unstable. Your critical days are the days when things are most likely to go wrong. People seem to lack coordination, and are therefore more accident prone on critical days. But remember: Biorhythms do not predict that anything good or bad will happen to you on your critical days, they only tell you that things are apt or more likely to be influenced by you or your en- viorment. These are the days that you could influence, if you were aware of them.