The golden book contains various chapters but those knowledge are only basic and lot of chapters are not profound. Dan already read about various materials so it was easy to understand general science for him ... in this era science isn't much developed because most of the knowledge comes from supreme beings 'mage' and they vastly researches on magic . Machinery knowledge and physics is too much limited and can be found only on advanced books which are protected by powerful clans . thou dan can research on molecular level with his Chip and insight but that's not all he can gather with self study . There are two types of human - ordinary human with no magical knowledge and Supreme being with profound magical knowledge aka mage. in the eyes of mages , ordinary humans are like ants but mages has near 0.25% fertility rate so mages need to rely on these ordinary people for future mages . there are also ordinary animals and magical animals , ordinary and magical trees but there are two types of magical beings one is natural from ancestors and other is artificial which mages created with experiments . In this planet humans are dominant race but there are also various races like giants , Titans , dragons , elf , goblins , orcs , dryads etc live in many parts . Even These races can be dominant in other planets and satellites .