As follus gach duil do na ceithre duilib na naduiribh & na n-inadaibh & na n-gluasachtaibh da beith contrara da ceili, oir idir gach ni da n-gluaisinn o medhon is i an tene as roluaithi acu & mar sin idir gach ni da n-gluaisinn co medhon as e an talam as roluaithi acu, & is mar sin ata an talam & an teine contrara da ceili ar son caili teasigheachta na teinedh ac oibriugad edromachta innte & ar son caili fuardhachta na talman ag oibriugad truimidheachta innte. Et tuig an tan aderar talam & teine no da duil ele da beith contrarda da ceili gorab iat caili na n-dul tuicter an tan sin da beit contrartha da ceili & nach iat a sustainnte. Oir adeir an feallsam in libro predicamentorum, substainte nicel est contrarium, oir ni fuil en ni contrarda ag an t-substaint. Oir is uime sin an trath aderar an tene da beth te tirim & an talam fuar tirim ata tes & fuacht in da duil sin contrara da ceile & atait aentaghach da ceile oir is i in tirmigacht oibrighes luas indtu.
Et is mar sin ata an t-aer & an t-uisci co h-aentadach & co h-asaentadhach da ceili ina cailib gnimhacha & atait co h-aentadhach is na cailibh fuilngteca .i. an fliche noch oibrighes a moille innta ar aen. Et atait asaentadach da ceili is na cailib gnimaca .i. a teasigacht oibriges edromacht is in aer & a fuardhacht oibriges tromidacht is in usci . Et as mar sin ata an tene & an t-uisci co h-asaentadach da ceili a na cailib gnimhacha & fuilngteca, oir as amlaid ata an tene te tirim luath edrum & is amlaid ata an t-uisci fuar fliuch mall trom. Et as follus fa deoigh na neice ac a fuil gluasacht direach co n-anait na inadaib nadurtha fein acht muna curtar as da n-ainneoin iat. Et an trat claechligter duil dib an duil ele tri nert na dula sin no an trat curter duil acu da h-ainneoin as a h-inadh nadurtha fein, mar as tusca dagib cuis no becan cunganta le no gan gabail re doni caisimpodh casluath obann d'innsaige a naduir & a inaid ducusa fein .
Et as follus aris gurab te gach uili ni gluaises o medhon & gorab fuar gach uili ni gluaiseas co medhon; et gorab tirim gan comortas ris gach ni luataiges an gluasacht & gurab fliuch gan comortas gach ni mallaighes an gluasacht . Et as mar sin da thuismid & d'ordaigh an tusmigteoir beannaithi an doman na ceithre duilibh.