The Explanation of Taiji’s Proper Practice (太極正功解) by Yáng​ Bān​hóu​ (楊班侯)

太極下乘武事解

太極者，圓也。無論內外，上下，左右，不離此圓也；太極者，方也，無論內外，上下，左右，不離此方也；圓之出入，方之進退，隨方就圓之往來也。方為開展，圓為緊湊。方圓規矩之至，其孰能出此以外哉？
如此得心應手，仰高鑽堅，神乎其神，見隱顯微，明而且明，生生不已。欲罷不能。

"Taiji is round. Regardless of internal or external, up or down, left or right, it will not part from the circle. Taiji is square. Regardless of internal or external, up or down, left or right, it will not part from the square. Enter and exit with the circle, advance and retreat with the square; follow the square to the circle back and forth. The square is the root for opening and extending, the circle is the root for tightenting and compacting. The circle and the square are the established standards, what could depart this standard?
In this way, proficiency will be achieved, and it will go higher by looking up and get harder by drilling down, it will be subtler and subtler, appearing concealed but actually manifest, brighter and brighter, growing incessantly and continuing without end. "

Based on the translation by Yang Jwing Ming (楊俊敏) presented in the book Tai Chi Secrets of the Yang Style (太極拳楊氏先哲秘要)

The explanation of Taiji’s Lower Level Martial Aspects (太極下乘武事解) by Yáng​ Bān​hóu​ (楊班侯)

太極下乘武事解

太極之武事，外操柔軟，內含堅剛。而求柔軟之於外，久而久之，自得內之堅剛。非有心之堅剛，實有心之柔軟也。所難者，內要含蓄堅剛而不施，外終柔軟而迎敵。以柔軟而應堅剛，使堅剛盡化無有矣。

"In the martial aspects of Taijiquan, the exterior steers soft and gentle and the interior keeps hard and strong. Over time, as softness is sought externally, one’s interior become hard and strong. One does not looks deliberately for hardness, one rather sincerely seeks softness. The difficulty is that the inside is required to keep strong and hard and not apply it, while the outside keeps gentle and soft when one meets an opponent. One uses softness to respond to strength and hardness in order to cause this strength and hardness to dissolve into nothingness."

其功何以得乎？要非粘黏連隨已成，自得運動知覺，方為懂勁。而後神而明之，化境極矣。夫四兩撥千斤之妙，功不及化境，將何以能？是所謂懂粘連，得其视聽輕靈之巧耳。

楊班侯

"How is this achieved? The key is to accomplish the training of attaching, adhering, connecting and following, obtain awareness and sensitivity of movement, then reach the Understanding Jin. At this point the spirit will clear and the conditions for a major transformation is reached. If the wonder of using four ounces to repel a thousand pounds and the conditions for this major transformation is still not yet reached, then what can one do? Apply what is called “understanding attach and adhere”, use the senses to skillfully find opportunities."

Based on the translation by Yang Jwing Ming (楊俊敏) presented in the book Tai Chi Secrets of the Yang Style (太極拳楊氏先哲秘要)

The Explanation of the Three Achievements in Scholarship and Martial Arts in Taiji (太極分文武事三成解) by Yáng​ Bān​hóu​ (楊班侯)

太極分文武事三成解

蓋言道者，非自修身，無由得也。然又分為三乘之修法。乘者，成也。上乘，即大成也；下乘，即小成也；中乘，即之者誠成也。

"When we talk about the path, there is no achievement without having a self-cultivation. The self-cultivation can be subdivided in three levels and three cultivation methods. The three levels are the achievements. The top level or great achievement, the low level or small achievement, and the middle level means the achievements of sincerity."

法分三修，成功一也。文修於內，武修於外。體育，內也；武事，外也。其修法，內外表裡成功，集大成，即上乘也；由體育之文，而得武事之武，或由武事之武，而得體育之文，即中乘也，然獨知體育，不入武事而成者，或專武事，不為體育而成者，即小乘也。

楊班侯

"Although, the cultivation methods are three, their achievement is one and the same. The scholarship is the internal cultivation; martial arts are the external cultivation. Education of the body is an internal cultivation while martial matters are external. The cultivation of that leads to internal and external achievement, allows to achieve the greatest achievement. If martial ability in martial arts is gained due to the study of education of the body or the education of the body is gained due to the martial capability of martial arts, then the middle level is achieved. If one is only aware of the education of the body and does not consider the achievement of the martial aspects, or conversely, those that look only into the martial aspects without looking for achieving the education of the body, those reach the low level of achievement."

Based on the translation by Yang Jwing Ming (楊俊敏) presented in the book Tai Chi Secrets of the Yang Style (太極拳楊氏先哲秘要)

Excerpt from The Achivements of the Sage (儒效) in the Xún​zǐ (荀子)

「不闻不若闻之，闻之不若见之，见之不若知之，知之不若行之；学至于行之而止矣。」

孔子

"Not hearing is not as good as hearing, hearing is not as good as seeing, seeing is not as good as knowing, knowing is not as good as acting; true learning continues until it is put into action."

Unless noted otherwise, all quotations of classical texts come from the Chinese Text Project. This translation was found in this blog.

Excerpt from the Great Learning (大學) in the Analects (論語)Trecho do Grande Aprendizado (大學) dos Analetos (論語)

「茍日新，日日新，又日新。」

孔子

"'If you can one day renovate yourself, do so from day to day. Yea, let there be daily renovation.'"

Unless noted otherwise, all quotations of classical texts and accompanying translations come from the Chinese Text Project

"'Se alguém pode se renovar, ele de fazê-lo um dia apos o outro. Que haja renovação todo dia.'"

Traduzido à partir da tradução para o inglês do Chinese Text Project

Excerpt from Words by a Brushwood Gate (柴門の辞)

古人の跡を求めず、
古人の求めたるの所を求めよ。

松尾芭蕉

"Seek not the paths of the ancients;
Seek that which the ancients sought."

Quoted from Wikiquote

Excerpt from Xian Jin (先進) in the Analects (論語)Trecho do Xian Jin (先進) dos Analetos (論語)

子貢問：「師與商也孰賢？」子曰：「師也過，商也不及。」曰：「然則師愈與？」子曰：「過猶不及。」

孔子

"Zi Gong asked which of the two, Shi or Shang, was the superior. The Master said, 'Shi goes beyond the due mean, and Shang does not come up to it.' 'Then,' said Zi Gong, 'the superiority is with Shi, I suppose.' The Master said, 'To go beyond is as wrong as to fall short.'"

Unless noted otherwise, all quotations of classical texts and accompanying translations come from the Chinese Text Project

"Zi Gong perguntou qual dos dois, Shi ou Shang, era superior. O Mestre disse, 'Shi vai além do que é razoável, e Shang nunca chega à ele.' 'Então,' disse Zi Gong, 'eu suponho que Shi seja superior.' O Mestre respondeu, 'Ir além é um erro tão grande como não completar a ação.'"

Traduzido à partir da tradução para o inglês do Chinese Text Project

Excerpt from Report of Guō Yúnshēn Sayings (述郭雲深先生言) in Boxing Concepts Explained Authentically (拳意述真)

十一則

練拳術不可固執不通。若專以求力。即被力所拘。專以求氣。即被氣所拘。若專以求沉重。即為沉重所捆墜。若專以求輕浮。神氣則被輕浮所散。所以然者。練之形式順者。自有力。內裏中和者。自生氣。神意歸於丹田者。身自然重如泰山。將神氣合一化成虛空者。自然身輕如羽。故此不可以專求。雖然求之有所得焉。亦是有若無實若虛。勿忘勿助。不勉而中。不思而得。從容中道而已。

郭雲深

"When practicing boxing arts, you must not have so much determination that it obstructs you. If you are obsessed with seeking to have strength, you will get jammed up by it. If you are obsessed with seeking to have energy, you will get clogged up by it. If you are obsessed with seeking to be heavy, it will weigh you down. If you are obsessed with seeking to be light, your spirit and energy will wander off.
Therefore the way to go about these things is to practice the postures smoothly, and then naturally there will be strength. When there is neutrality within, it will naturally produce energy. When your spirit and intention return to your elixir field, your body will naturally be as heavy as Mt. Tai. When your spirit and energy merge into one and transform into emptiness, your body will naturally be light as a feather.
Thus you must not obsessively seek, even though there may be something to be gained through the seeking. Look upon that something as if it is nothing, treating its substantiality as insubstantial. Neither forget about it nor assist it. Do not strive for it and you will hit the target. Do not fixate on it and you will obtain it. Being patient and balanced is all you need."

Excerpt from the translation by Paul Brennan, to be found in the Brennan Translation blog.

Excerpt from Wei Zheng (為政) in the Analects (論語)Trecho do Wei Zheng (為政) dos Analetos (論語)

學而不思則罔，思而不學則殆。

孔子

"Learning without thought is labor lost; thought without learning is perilous."

Unless noted otherwise, all quotations of classical texts and accompanying translations come from the Chinese Text Project

"Aprender sem refletir é perda de tempo; refletir sem aprender é perigoso."

Traduzido à partir da tradução para o inglês do Chinese Text Project

Excerpt from The Full Understanding of Life (達生) in Zhuāng zi (莊子)Trecho de A Compreensão Completa da Vida (達生) do Zhuāng zi (莊子)

紀渻子為王養鬥雞。十日而問：「雞已乎？」曰：「未也。方虛憍而恃氣。」十日又問。曰：「未也。猶應嚮景。」十日又問。曰：「未也。猶疾視而盛氣。」十日又問。曰：「幾矣。雞雖有鳴者，已無變矣，望之似木雞矣，其德全矣，異雞無敢應者，反走矣。」

莊子

"Ji Xing-zi was rearing a fighting-cock for the king. Being asked after ten days if the bird were ready, he said, 'Not yet; he is still vain and quarrelsome, and relies on his own vigour.' Being asked the same after other ten days, he said, 'Not yet; he still responds to the crow and the appearance of another bird.' After ten days more, he replied, 'Not yet. He still looks angrily, and is full of spirit.' When a fourth ten days had passed, he replied to the question, 'Nearly so. Though another cock crows, it makes no change in him. To look at him, you would say he was a cock of wood. His quality is complete. No other cock will dare to meet him, but will run from him.'

Unless noted otherwise, all quotations of classical texts and accompanying translations come from the Chinese Text Project

"Ji Xing-zi estava adestrando um galo de briga para o rei. Após dez dias ao ser perguntado se a ave estava pronta, ele respondeu 'Ainda não, ele ainda é vaidoso e brigão, e conta com o próprio vigor.' Ao ser perguntado novamente após mais dez dias, ele respondeu: 'Ainda não, ele ainda responde ao canto e à aparência de outra ave.' Após outros dez dias, ele respondeu: 'Ainda não. Ele ainda tem raiva no olhar e demonstra exuberância.' Quando um quarto período de dez dias passou, ele respondeu à questão: 'Quase. Apesar dos outros galos cantarem, ele não se altera. Ao olhá-lo, poderia-se dizer que ele é um galo de madeira. Sua virtude é completa. Nenhum outro galo vai se atrever a provocá-lo, e ao contrário irão fugir dele'"

Traduzido à partir da tradução para o inglês do Chinese Text Project

Excerpt from What comes from without (外物) in Zhuāng zi (莊子)

荃者所以在魚，得魚而忘荃；蹄者所以在兔，得兔而忘蹄；言者所以在意，得意而忘言。吾安得忘言之人而與之言哉？

莊子

"The fish trap exists because of the fish; once you've gotten the fish, you can forget the trap. The rabbit snare exists because of the rabbit; once you've gotten the rabbit, you can forget the snare. Words exist because of meaning; once you've gotten the meaning, you can forget the words. Where can I find a man who has forgotten words so I can have a word with him? "

Unless noted otherwise, all quotations of classical texts and accompanying translations come from the Chinese Text Project

The Secret

練

Within the Internal Martial Arts lore, there is an anedocte that highlights the importance of practice. It says that when Sūn Lùtáng (孫祿堂) was on his deathbed, his students asked him what was the secret for reaching a high level of Kung Fu. As Sūn Lùtáng was unable to speak, he raised his palm and with the other hand, drawn an imaginary character "practice" - liàn (練) on it.
In the introduction of the translation of Study of Xing Yi Quan (形意拳學) by Benjamin Lo, Sūn Jiànyún (孫劍雲), Sūn Lùtáng's daughter, states that the story is apochryphal and false. She goes on to say that it does convey the opinion of Sūn Lùtáng nevertheless. This is also an observation that I had from any serious teacher.
It is a fine reminder of the prime place of practice (練), relegating any other activity to a secondary place. Activity as reading books, watching videos, or writing this blog for that matters, are diversions to the one core activity of the serious practicioner.
However, the story stops short of giving further clues of what should constitute practice: its scope (what kind of exercices? how many styles?), the relative importance of frequency and quantity, how much practice is enough, under what conditions it is wise to practice and not practice, and so on. Some of the more esoteric aspects are sometimes adressed, like the notion of practicing facing north or early in the morning, without however a general orientation on how to practice.
In fact, what I would call the methodology of practice is something that is not systematically approached in the literature and in classes in general. It is particularly hard for a beginner to find himself all alone and decide what she should practice. In my opinion, this point is the main first obstacle for someone that wishes to become a serious practitioner.

Excerpt from Knowledge rambling in the North (知北遊) in Zhuāng zi (莊子)

大馬之捶鉤者，年八十矣，而不失豪芒。大馬曰：“子巧與？有道與？”曰：“臣有守也。臣之年二十而好捶鉤，於物無視也，非鉤無察也。是用之者，假不用者也以長得其用，而況乎無不用者乎！物孰不資焉？”

莊子

"The forger of swords for the Minister of War had reached the age of eighty, and had not lost a hair's-breadth of his ability. The Minister said to him, 'You are indeed skilful, Sir. Have you any method that makes you so?' The man said, 'Your servant has (always) kept to his work. When I was twenty, I was fond of forging swords. I looked at nothing else. I paid no attention to anything but swords. By my constant practice of it, I came to be able to do the work without any thought of what I was doing. By length of time one acquires ability at any art; and how much more one who is ever at work on it! What is there which does not depend on this, and succeed by it?'"

Unless noted otherwise, all quotations of classical texts and accompanying translations come from the Chinese Text Project