is the name of a late 12th-century treatise on English treasury procedures by Richard FitzNigel. The first book begins as follows:

In the twenty-third year of the reign of King Henry II, while I was sitting at the window of a tower next to the River Thames, a man spoke to me impetuously, saying: "Master, hast thou not read that there is no use in science or in a treasure that is hidden?"

When I replied to him, "I have read so."

Straightway he said: "Why, therefore, dost thou not teach others the knowledge concerning the exchequer which is said to be thine to such an extent, and commit it to writing lest it die with thee?"

I answered: "Lo, brother, thou hast now for a long time sat at the exchequer, and nothing is hidden from thee, for thou art painstaking. And the same is probably the case with the others who have seats there."

But he, "Just as those who walk in darkness and grope with their hands frequently stumble, so many sit there who seeing do not perceive, and hearing do not understand."

Then I, "Thou speakest irreverently, for neither is the knowledge so great nor does it concern such great things; but perchance those who are occupied with important matters have hearts like the claws of an eagle, which do not retain small things, but which great ones do not escape."

And he, "So be it: but although eagles fly very high, nevertheless they rest and refresh themselves in humble places; and therefore we beg thee to explain humble things which will be of profit to the eagles themselves."

Then I, "I have feared to put together a work concerning these things because they lie open to the bodily senses and grow common by daily [use]; nor is there, nor can there be in them a description of subtile things, or a pleasing invention of the imagination."

And he, "Those who rejoice in imaginings, who seek the flight of subtile things, have Aristotle and the books of Plato; to them let them listen. Do thou write not subtile but useful things."

Then I, "Of those things which thou demandest it is impossible to speak except in common discourse and in ordinary words."

"But," said he, as if aroused to ire, -- for to a mind filled with desire nothing goes quickly enough, -- "writers on arts, lest they might seem to know too little about many things, and in order that art might less easily become known, have sought to appropriate many things, and have concealed them under unknown words: but thou dost not undertake to write about an art, but about certain customs and laws of the exchequer; and since these ought to be common, common words must necessarily be employed, so that style may have relation to the things of which we are speaking. Moreover, although it is very often allowable to invent new words, I beg, nevertheless, if it please thee that thou may'st not be ashamed to use the customary names of the things themselves which readily occur to the mind, so that no new difficulty from using unfamiliar words may arise to disturb us."

Then I, "I see that thou art angry; but be calmer; I will do what thou dost urge. Rise, therefore, and sit opposite to me; and ask me concerning those things that occur to thee. But if thou shalt propound something unheard of, I shall not blush to say 'I do not know.' But let us both, like discreet beings come to an agreement."

And he, "Thou respondest to my wish. Moreover, although an elementary old man is a disgraceful and ridiculous thing, I will nevertheless begin with the very elements."

(Paragraph breaks and a few slight alterations, including some capitalization, added.)