Complex sentence: Good health constitutes a proper mixing of the humors, and if there is any imbalance then it would result in characteristic patterns of disease or illness that cause the ill individual to become dry, cold, hot, wet, or a combination of these states.
Split into simpler sentences: Good health constitutes a proper mixing of the humors, and if there is any imbalance then it would result in characteristic patterns of disease. Illness is believed to result from a humoral imbalance that caused the individual to become dry, cold, hot, wet, or a combination of these states.