When upholding right speech we do so because it goes for us in a right direction. So that is a wise thing to do. To that extend this is a right view which, structurally thus, comes first. And this is what the noble eightfold way tells us. And doing so we'll also want to watch our mind, which does take some exertion and concentration, else our thoughts would be all over the place. Our speech could then turn out to be not right. So working on one member is then not without involving the others. Hence there is no need to worry about getting right view first, or fear about missing out by seeing sīla as a surrogate start. That unclarity itself is an obstruction. We do however, need to be well informed and we do need to be paying attention; this supports right view.
Magga is often translated as path. I use path for paṭipadā and way for magga, so I have a noble eightfold way. If a path has steps, what would you say a (high) way got? Right, lanes. To illustrate this highway with eight lanes we set up a wooden train set for kids. As it is not so intuitively to set up we have to get ourselves well informed. If we build this highway we must know where we are heading to right? So lets say we want to go to ... well, to the outside, so our highway is then build in accordance to this path. It is set up by glueing eight tracks together, as lanes, prolonged with the remaining tracks glued to their ends. Each track is magnetic and got its own little wooden magnetic train car with a small eye bolt on top. Here we run a wire through so they are all attached. We add the accompanied name tags to the appropriate lanes and when the cars have been placed on their tracks all is set and ready to go.
On this path our highway advances through three areas, masses. The first mass we call sīla, the second mass samādhi and the third mass paññā. Thus when moving train car number 3, at 'right speech', all cars advance through the mass of sīla. Sīla is behaviour and samādhi concentration. When we leave the mass of Behaviour and arrive in the mass of Concentration it doesn't mean Behaviour is then suddenly not intact anymore, as if Concentration is without Behaviour. The mass of Concentration is here then build on top of the mass of Behaviour. Had we not been informed we would have found an outside at a horizontal level which in the long run, as the earth is round, would cause us to be circling around. Now our highway first goes through the ceilings, before going through the roof.
Hence we can find in MN44:
'Yet lady, is the noble eightfold way inclined or uninclined?'
OK the noble, Mr Visākha, eightfold way is inclined.OK now lady are, by the noble eightfold way, three masses included, or is by three masses the noble eightfold way included?
OK not, Mr Visākha, are by the noble eightfold way three masses included; and OK by three, Mr Visākha, masses is the noble eightfold way included.
What is said here is that these three mass are not included by the noble eightfold way, thus not a lower or equal level, but they include the noble eightfold way, thus a higher level. The mass of sīla then got a higher level of right speech, a higher level of right action, a higher level of a right way of life, plus the other members of the way which have not gone higher yet. It is as if several train cars, e.g. 3, 4 and 5, are being pushed, leaving some distance between them and the others.
So what these little train cars represent is this advancement, cultivation, on the path. Cultivation on the path will gradually give a more refined, advanced, noble eightfold way; cultivation pours over by cultivation. For example not-lying does takes some exertion and concentration. If we don't talk we don't tell a lie, let alone when thoughts and thinking have stopped, the second radiance jhāna, which thus takes a higher level of exertion and concentration; with right concentration often the radiances are mentioned but right concentration does not equals right radiance, what is then addressed is this culmination. Or with not-stealing; if we don't take any things which are not ours there is no stealing, and things which are not ours include the five masses and without even holding them the final yokes are cut; which takes this higher level of wisdom. And this is possible because it is the noble eightfold way that is inclined.
This noble eightfold way is inclined, as its members are inclined, which allows for a gradual training on gradual levels. Thus when on the way the further training is undertaken to advance in behaviour (adhisīla), advance in mind (adhicitta) and advance in wisdom (adhipaññā); the threefold training. A refinement on refinements. And with this refinement, this difference in sīla, samādhi, paññā, is there the difference in persons, the sottāpanna, sakadāgāmin, anāgāmin and arahant.