Just like when you learn English, you can speak English. Those who do not learn English, of course, do not understand you, while those who do, understand you as soon as you open your mouth. You can question and answer each other in a lively and distinct way, whereas those who do not know English, cannot. This is just a question of knowing and not knowing. It is the same with the many sciences in our world.
Some people study medical science and some study engineering.
They become experts and understand what each other says and does, but outsiders like us do not understand them. Some sciences are supraworldly, such as those related to research on life on other planets and finding out about our past and future. It is in a very, very high world. I am not referring to the distance, but rather, to the highest supreme world. There is nothing on this Earth that can compare with it.