some help on Musashi's book of five rings?

Please note that the English interpretation is imprecise; however, here are the quotes to which i believe you are referring. I believe the following passages are those to which you refer; however, I have included much of The Way of Strategy wherein carpentry is discussed. The passages immediately following have relevance to posture and form in that the discussion regards "sharpening your own tools" and ensuring the essentials are properly formed.

Like a trooper, the carpenter sharpens his own tools. He carries his equipment in his tool box, and works under the direction of his foreman. He makes culumns and girders with an axe, shapes floorboards and shelves with a plane, cuts fine openwork and carvings accurately, giving as excellent a finish as his skill will allow. This is the craft of carpenters. When the carpenter becomes skilled and understands measures he can become a foreman.

The carpenter's attainment is, having tools which will cut well, to make small shrines, writing shelves, tables, paper lanterns, chopping boards and pot-lids. These are the specialities of the carpenter. Things are similar for the trooper. You ought to think deeply about this.

The attainment of the carpenter is that his work is not warped, that the joints are not misaligned, and that the work is truly planed so that it meets well and is not merely finished in sections. This is essential.

A book of Five Rings

The Way of Strategy

Fourthly the Way of the artisan. The Way of the carpenter is to become proficient in the use of his tools, first to lay his plans with a true measure and then perform his work according to plan. Thus he passes through life. These are the four Ways of the gentleman, the farmer, the artisan and the merchant.

Comparing the Way of the carpenter to strategy

The comparison with carpentry is through the connection with houses. Houses of the nobility, houses of warriors, the Four houses, ruin of houses, thriving of houses, the style of the house, the tradition of the house, and the name of the house. The carpenter uses a master plan of the building, and the Way of strategy is similar in that there is a plan of campaign. If you want to learn the craft of war, ponder over this book. The teacher is as a needle, the disciple is as thread.

You must practice constantly. Like the foreman carpenter, the commander must know natural rules, and the rules of the country, and the rules of houses. This is the Way of the foreman.

The foreman carpenter must know the architectural theory of towers and temples, and the plans of palaces, and must employ men to raise up houses. The Way of the foreman carpenter is the same as the Way of the commander of a warrior house.

In the contruction of houses, choice of woods is made. Straight un-knotted timber of good appearance is used for the revealed pillars, straight timber with small defects is used for the innter pillars. Timber of the finest appearance, even if a little weak, is used for the thresholds, lintels, doors, and sliding doors, and so on. Good strong timber, though it be gnarled and knotted, can always be used discreetly in construction. Timber which is weak or knotted throughout should be used as scaffolding, and later for firewood.

The foreman carpenter allots his men work according to their ability. Floor layers, makers of sliding doors, thresholds and lintels, ceilings and so on. Those of poor ability lay the floor joist, and those of lesser ability carve wedges and do such miscellaneous work. If the foreman knows and deploys his men well the finished work will be good.

The foreman should take into account the abilities and limitations of his men, circulating among them and asking nothing unreasonable. He should know their morale and spirit, and encourage them when necessary. This is the same as the principle of strategy.

The Way of Strategy

Like a trooper, the carpenter sharpens his own tools. He carries his equipment in his tool box, and works under the direction of his foreman. He makes culumns and girders with an axe, shapes floorboards and shelves with a plane, cuts fine openwork and carvings accurately, giving as excellent a finish as his skill will allow. This is the craft of carpenters. When the carpenter becomes skilled and understands measures he can become a foreman.

The carpenter's attainment is, having tools which will cut well, to make small shrines, writing shelves, tables, paper lanterns, chopping boards and pot-lids. These are the specialities of the carpenter. Things are similar for the trooper. You ought to think deeply about this.

The attainment of the carpenter is that his work is not warped, that the joints are not misaligned, and that the work is truly planed so that it meets well and is not merely finished in sections. This is essential.

If you want to learn this Way, deeply consider the things written in this book one at a time. You must do sufficient research.

I have a comparison of The Way to Carpentry (Earth book):

"In the construction of houses, choice of woods is made. Straight un-knotted timber of good appearance is used for the revealed pillars; straight timber with small defects is used for the inner pillars. Timber of the finest appearance, even if a little weak, is used for the thresholds, lintels, doors, and sliding doors, and so on. Good strong timber, though it be gnarled and knotted, can always be used discreetly in construction. Timber which is weak or knotted throughout should be used as scaffolding, and later for firewood."

"Everything can collapse. Houses, bodies, and enemies collapse when their rhythm becomes deranged."

My digital copy (searchable) is incomplete. Perhaps someone has a better copy and can add to these?