'Cheon' is one of four categories with 'Ki'(氣), 'Do'(道), ‘Ri'(理). Specially 'Cheon' meaned sky is so important that most of philosophers have referred to it. 'Cheon' is widespread, so it has been the object of the astronomers and subject of the philosophers. All recognize the conception definitely and consistently, in the other hand some vaguely, someone give different conceptions. Therefore this paper is written with a view to right recognition of the conception and relationships with the human by the study of significance changes by the times.

Ki is the important conception of Chinese philosophy, many of philosophers have discussed it. So the meaning of it is various in accordance with the times and the scholars. And it has been discussed not only in the sphere of philosophy but medicine, astronomy, g eography, society and culture ; therefore we can't understand the Oriental studies without the comprehension of it. Above all, the Oriental-medicine is based on the principles of it, that is to say 'Ki-medicine'. There are Ki of a letter, Ki of a philosophy, Ki of a nature and Ki of the human body according to the recognition process from that time on the ancient. This paper is written with the view of the right understanding about it by the comparison of various theories dealed with it.

For the purpose of developing Korean Herbalogy with the plants of Caryophllcceae which grow wild and is planted in Korea, the these and writings on herbalogy, from literature of successive generation, have been thoroughly investigative and the results obtained were as follows: 1. There were totaled to 20 genera and 124 species in Korea and among them midical plants are 11 genera, 30 species, some 24% in total. 2. According to the oriental names which can be used for medical purpose, the medical plantss belonging to the Caryphllaceae family were classified as Herba 11, Radix 7, Foilum 2, Semen, Flos, Rhizoma 1 each 3. According to sum of 124 species in Caryophllaceae family, they were classified into Cerastium genera 18, Dianthus gemera 16, Pseudos tellaria genera, Lychnis genera, Stellaria genera 12 each, Melandry um genera 11, Silene genera 10, Minuaria genera 8, Gypsophila genera, Sagina genera 5 each, Arenaria genera, Cucubalus genera 3 each, Spergual genera, Vaccaria genera 2 each, Agorostema genera, Amnodenia genara, Moehringia genera, Myosoton genera, Honkenya genera 1 each. Thus it was noticed that Cerastium genera was main kind 4. According to the number of species of the orgin plants about each chinese materia medicals, they were classified into HERBA DIANTHI 4, RADIX PSEUDOSTELLARIAE 3, SEMEN VACCARIAE 5, RADIX GYPSOPHILAE 4. 5. According to the properties and principal curative action, they were classfied into drugs for treating febrifugal and removing heat from blood, Diuretocs 6 each, Drugs for treating febrifugal and detoxicant 2, Drugs for invigorating blood, circuration and eliminating blood stasis 3, tonics 1, easing joint movement 1, stimulation of lactation 44. 6. According to nature and flavour of medical plants, they were classified into warmth, heat; each 3, cold, cool; 11each, balance 3 and unidentifird 2. Thus it was noticed that cold and cool is the main in nature and flavour of medical plants. 7. Toxic drugs were none. From this results, It was revealed that the plants for medical purpose in Caryophllaceae was 24% of the whole, in which Herba was mostly abundunt. It is considered that may expriements and clinical approches must be continued to use Caryophllaceae plants widely.