Fire, the sixth external pathogen, can cause the diseases called warm heat and summer heat. Fire is also one of the life forces transformed by yang energy into what is called physiological fire. There are different types of physiological fire, including monarch fire, minister fire, and lesser fire. Fire can also refer to a manifestation due to pathological change, which means that all kinds of external pathogenic energies, including the seven emotions (see below) and internal injuries, can transform into fire and turn into pathological fire. In addition, fire can be differentiated into excess fire and deficiency fire. Excess fire is due to an excess of external pathogenic energies, which are mostly seen in acute hot diseases, with such symptoms as high fever, excessive perspiration, thirst, insanity, pink eyes, red complexion, discharge of blood from the mouth, nosebleed, red tongue, yellowish, and dry coating of the tongue, and rapid and forceful pulse. Deficiency fire is due to an exhaustion of yin fluids, which is mostly seen in chronic wasting diseases, with such symptoms as being hasty, insomnia, seminal emission with erotic dreams, night sweats, cough with sputum containing blood, red tongue with scant coating, and fine-rapid or deficiency-rapid pulse.