The crowd watching the excitement on the side suddenly laughed, and praised Lu Qiujian's wit, but Mu You's desire to sing a song about Wu Qianlian made him a little regretful.

"Hey!", the man on the opposite side couldn't hold back his face, and he wanted to quarrel with Lu Qiujian with a red face; at this time, the Zen master next to him couldn't help it, and hurriedly persuaded him, "Don't be angry, the two donors are reasonable, but things in this world are like paper, there are two sides, otherwise you look for it, where is there only the front and no back of the paper!"

The man on the opposite side estimated Lu Qiujian's height and combat effectiveness, sat down with the persuasion of the Zen master, and muttered, "I'll give the master a face today, and I won't care about you!"

Lu Qiujian became interested in this Zen master, interesting, there are not many Buddhist scriptures in his mouth, but he expounds the truth with the things that can be seen everywhere around him, and it seems that he has some real skills in his stomach.

Do you want to tease him? Lu Qiujian rolled his eyes and asked as he took out a notebook, "Master, are you saying that there is no paper in this world that only has the front and no back?"

"That's true!", replied the master firmly.

Lu Qiujian tore off a piece of paper, twisted one end and glued the other end together, and made a simple Möbius ring, "Master, look, this piece of paper has only one side! If you don't believe it, you can use a pen to draw a line along the surface of the paper, and this line will definitely intersect!"

"Mobius Ring!", the little girl opposite blurted out, "When I was in school, the teacher said that there is indeed only one side to this!", after saying that, she took out her pen and drew a line in the middle of the note, and then kept following the line of defense, and finally the beginning and end of the line converged.

The corner of the Zen master's mouth twitched, "Young man, your mind is already filled with preconceived opinions, why don't you pour out a little space to decorate something new? The human brain is like a bottle, there is always an end, and you must first pour out the contents before you can fill it with new ones!"

"Well, I think there are a lot of new things in the master's mind!", it is indeed different from those fake monks who can only cheat money, at least there is a worldly insight in the temperament of speaking, "But master, are you sure that the bottles have an end?"

"As long as this is a bottle, there is a distinction between the inside and the outside, and the inside leads to the end!", the master was not as calm as the first time at this time.

Lu Qiujian scribbled on the notebook, and after a while, a Klein bottle was drawn by him (in fact, the Klein bottle is a curved surface that can only be truly expressed in the four-dimensional space, just take a look here), and handed it to the Zen master, "Master, what do you think of this bottle? Is there a distinction between inside and outside? Is there an end?"

There is a hole in the bottom of the bottle that lengthens the neck of the bottle and twists into the inside of the bottle and then connects to the hole at the bottom, so that the bottle has no distinction between inside and outside, and a fly can fly directly from the inside of the bottle to the outside without having to cross the surface.

Seeing that the bottle's face changed three times, the Zen master recited the Heart Sutra several times in his heart before he could hold back Mu You's anger, he took a deep breath and took the notebook in Lu Qiujian's hand, and drew a picture on it, on which were several columns with a wooden plank, he put down the pen and said, "Young man, you can't be too angular, sometimes you have to be more rounded; you see, the wheels work together to keep the board moving smoothly, can you find the shape of the edges and corners to make the board move smoothly?"

"This can be had!", Lu Qiujian replied confidently, he drew a row of wooden sticks with a cross-section of the Lelo triangle next to the picture drawn by the Zen master, and also drew a wooden board to lay on it, "You see that if you look at this, there are edges and corners that can also make the wooden board on this move forward smoothly without shaking!"

"How is this possible?", the Zen master asked with a look of disbelief, "how is it possible that such a thing will keep the wooden board from shaking?

"I've seen this thing in the factory!", someone in the lively crowd next to him spoke, and a middle-aged man wearing the uniform of a car factory stood up, "This thing is called the Leylo triangle, the Leylo triangle is a fixed-width curve, and it will not shake up and down when it is used to carry things." Compared with the common piston reciprocating engine, the rotary engine has low vibration, high speed and simple structure, which is much better!"

Amitofu, who meowed, can't get along with Lao Gu today! After reciting the Heart Sutra N times again, the depression in my heart was eliminated, and I don't believe that I can't argue with you today! His eyes rolled, and he had an idea, and he put his bowl on the small table, "Look at my bowl, what method will you use to fill it?"

"It looks like it's almost enough to put two pounds of stones!"

"Is that full?"

"There is still a gap between the pebbles and the pebbles, you can put some more sand!", this is probably to wait until I can no longer load things, persuade me to throw away some of the things in my head, right? Lu Qiujian guessed.

"And then, is it full now?"

"No, it's not full yet, you can pour some more water into it!", Lu Qiujian continued to answer!

"Is it full after pouring it?"

"No, you can add salt to saturation!"

"After adding salt, is it full?", recited the Heart Sutra eight times before the Zen master asked this sentence.

"No, you can also add hydrofluoric acid to dissolve the sand and gravel, then evaporate the residual liquid, and then add high temperature melting, and then reduce it to silicon elemental matter and make flash memory full of data!", Lu Qiujian is still calm.

The Zen master finally couldn't help it, and the green tendons of his hand holding the bowl flared up, and he was about to turn his face! At this time, the train just arrived at the station, "The old man has arrived home, and he is not as knowledgeable as you!", the Zen master ran away as if he was running away amid laughter.

When I returned to the temple, I drank eight bowls of herbal tea in a row to feel better, and called my apprentice, "You go and make me a fast wooden card!"

"Yes, Master, what kind of wooden plaque do you want?", the disciple asked obediently.

"It's good to be eye-catching, let the carpenter Li at the corner of the street do it! He hasn't given the incense money last time!", the master's memory is very good, "There are seven words written on it: science students are not allowed to enter!"

The master was busy making signs, and Lu Qiujian had also arrived at his destination, putting his notebook and dictionary back in his bag, coming out of the train station, looking at the strange and familiar city, reaching out to stop a taxi, reporting the address of his home, and then closing his eyes and thinking about how to get along with his parents after returning home!

10,000 plus more, a few at home quickly finish the water, and then go back to school to hold a report meeting and pretend to be forced.