Samma Ditthi is in short Right understanding. Right understanding is explained as the knowledge of the four noble truths. In other words, it is the understanding of oneself as one really is, because, as the Rohitassa Sutta states, these truths are concerned with the "one-fathom long body of man." The key-note of Buddhism is this right understanding.
Consider the following statement: Pemato jayati soko, pemato jayati bhayam. [From affection springs grief, from affection springs fear]. Conventional minds will recoil to the idea - as it indeed did when the Buddha said it. The truth and meaning of Dhamma becomes a private experience by the wise only when there is insight or vipassana. But vipassana depends on samadhi or concentration. And samadhi depends on Samma-ditthi. Thus, everything in Dhamma is connected. Why is that? The Buddha is speaking, albeit in diverse ways, only of one thing and one thing alone – dukkha and the cessation of dukkha.
One pre-requisite of one coming to ‘Right View’ (Samma Ditti) is learning to welcome advice of the Supreme Buddha with delight. We must not treat even a single verse of Dhamma as being plain and simple. We must learn to treat the Noble Dhamma as supreme. We must consider this Dhamma to be the most profound. One would ask as to why should we learn to perceive it in that way? It is because this Noble Dhamma is Svākkhāto (it is well proclaimed). Nothing needs to be corrected in this Dhamma and nothing can be discarded on the basis that it is too plain and simple (if one understands this quality, then this person comes to Samma Ditti— right view). This is why we must hold dear the advice we receive and use that noble advice to discipline ourselves than vice-a-versa.
In its fullest measure right view involves a correct understanding of the entire Dhamma or teaching of the Buddha, and thus its scope is equal to the range of the Dhamma itself. But for practical purposes two kinds of right view stand out as primary. One is mundane right view, right view which operates within the confines of the world. The other is supramundane right view, the superior right view which leads to liberation from the world.
Mundane right view involves a correct grasp of the law of kamma, the moral efficacy of action. Its literal name is "right view of the ownership of action", and it finds its standard formulation in the statement: "Beings are the owners of their actions, the heirs of their actions; they spring from their actions, are bound to their actions, and are supported by their actions. Whatever deeds they do, good or bad, of those they shall be heirs."
This superior right view leading to liberation is the understanding of the Four Noble Truths. It is this right view that figures as the first factor of the Noble Eightfold Path in the proper sense: as the noble right view. Thus the Buddha defines the path factor of right view expressly in terms of the four truths: "What now is right view? It is understanding of suffering (dukkha), understanding of the origin of suffering, understanding of the cessation of suffering, understanding of the way leading to the cessation to suffering."