Isn't Buddhist insight practice more scientific than the so-called scientific method? All enlightened beings since the first Arahant have confirmed the four noble truths and the noble eightfold path to be true through their own experience. So there is a community of Ariya Sangha who accept them to be the truth. Isn't this better than the peer review evaluation used in the "Scientific Method"? Many findings that were previously accepted under the scientific method as scientific knowledge have since been rejected, but no enlightened being has ever changed his mind to say that the four noble truths or the noble eightfold path are false.
I like this question (I've cleaned it up a bit for clarity).

Basically, what it's asking is whether Buddhist practice should be considered more or less scientific than the scientific method. I've tried to make this argument before - most recently in a talk at the University of South Florida. The concepts are still a bit vague, but I think the argument is sound.

The problem is in defining what constitutes valid scientific inquiry, and what is meant by knowledge.

In material science, the frame of reference is an interpersonal environment where the requirement for evidence is third-person verifiability. A theory is only considered scientific if there is some means of impersonal falsifiability (i.e. can it be disproved by a third person through experimental means). Observations should be made by an impartial third party (preferably a double blind where the observer and the administer are two different people) reproducible by others undertaking the same experiments as the original observer.

In insight meditation, the frame of reference is internal and so any observations must be made by the individual themselves. Thus, their observations are seen as unreliable by the modern scientific community. Within the context of an interpersonal frame of reference, this makes sense.

An argument in defence is that the frame of reference in Buddhism is not interpersonal - i.e. it doesn't matter whether I "really" made observation X; what is important is that I perceived it as being observation X. Using this premise as a basis for investigation, I think it is still possible to separate objective observations from subjective ones, though it is of course more difficult.

The difficulty I've found is in explaining Buddhist insight practice as objectively objective; how can one prove that the act of reminding oneself "seeing" actually allows oneself to be completely objective? I think there is some logic behind the fact that reminding oneself of the inherent nature of the observation creates objectivity, but it is still an uncertain hypothesis.

I think the answer lies in the expected outcome; we would expect experimentation A to be objective if it brought about consistent, reproducible (again, only by the individual) results in all situations. Subjective experimentation would lead to inconsistent results. Objective experimentation would also be expected to lead to clear definition of the nature of the objects of observation (i.e. object X appears to invariably display property A).

Such principles could then be verified between experimenters; interviewing individual meditators could potentially lead to patterns of observations of the sort mentioned above.

The point of all this is that there is at least a quasi-scientific aspect to personal meditation; it need not be discarded as purely subjective, especially since it is acknowledged that the mind does seem to follow orderly principles.

Where this all gets interesting is at the level of enlightenment, where a meditator actually claims to be certain of their observations, due to overwhelming personal evidence of its truth. Obviously such certainty is useless in an interpersonal frame of reference, but for the meditator themselves, such statements can perhaps be examined and differentiated between. For example, a meditator may come to a certainty through faith, in which case it will be of a specific quality that must be different from that arrived at through overwhelming evidence. The former would be subject to alteration in the face of further observation (or even over time), whereas the latter would only be confirmed through further observation.

From the frame of reference of the individual, then, it wouldn't matter what anyone else said about the subjectivity or invalidity of their claim; since their every observation reaffirmed the certainty of their conclusion, they would feel their claim to be scientifically arrived at, and it would be impossible to shake them of that conviction without resorting to tactics like brainwashing.

Further, once a meditator attains nibbana, even brainwashing would be unable to shake their conviction, since their very being would be changed by the realization; not clinging to body and mind, they would be impervious to all attempts at subversion.

The point here is that they would regard their certainty as scientifically gained; i.e. through what they felt to be objective observation. The obvious criticism is that anyone can claim such objectivity, even in the case of those under the influence of subjective partiality. Again, this is only important in the case of an interpersonal frame of reference. Within one's own mind, it is completely up to the individual to critique their own observations, since it is indeed only they who can possibly determine whether an observation is objective or not.

We therefore place the onus on the individual to critique themselves, and assume that there is indeed a means by which one can distinguish a subjective state from an objective one. Defining criteria by which one could undertake such discernment would assumedly look a lot like the Buddha's own methodology of separating experience out into constituents parts and subjecting each aspect to rigorous inspection to determine natures of each aspect and relationships between aspects.

In the end, then, the idea would be that the meditator would be able to cultivate an increasingly objective outlook on their own experience, eventually culminating in a paradigm shift from subjective partiality to objective observation, at which point they would intuitively understand the nature of observable phenomena.

The purpose of this would be a heightened level of "knowledge" (i.e. certainty) about a given claim, e.g. "no experience is worth clinging to". The idea here is that such knowledge would be weaker without such cultivation.

The question, then, is whether such knowledge is superior to material scientific knowledge. Obviously, it is inferior in the sense that it cannot be directly shared with others, but given the premise that anyone can undertake the same practices, with the claim that they will achieve the same level of knowledge, even this is a poor argument. Equally obvious is the superiority in the sense of the level of individual certainty which, according to an arahant themselves, would be absolutely and eternally unshakable.

The only really valid criticism is as to whether such certainty can be in any way distinguished from simple brainwashing. The defence against this criticism, I think, lies in the ability of an individual to distinguish between states of knowledge; in fact, there is the sense that brainwashing is not knowledge in any real sense of the word, since the certainty would go against one's own experience.

Which is another key point (sorry for my meandering thoughts) - that there are two levels of observation - the conceptual and the ultimate. Whereas the nature of and relationship between concepts can be changed, those of the building blocks of experiential reality are immutable. 

For example, an experimenter may administer an experience to trick the subject into finding a correlation between stimulus A and result X where there wouldn't naturally be one (e.g. A Clockwork Orange). What the experimenter cannot do is affect the perceptions of the individual itself. So, while it is possible to brainwash someone into believing that violence is a cause of nausea, it is not possible to alter their observations of the experience of the violence and the nausea, because the building blocks that make up the experience cannot be changed, nor can their relationships. This seems like a reasonable premise, one which allows an individual to potentially discriminate between brainwashing and true knowledge.

Obviously, since there is no potential for peer review, such discrimination is extremely unlikely to occur in the average individual, hence the esteem given to the Buddha; still, this doesn't invalidate the claim that it is technically possible, given the right tools and determination. The important point is that it is not only possible, but absolutely preferable given the inherent strength of such knowledge, even over peer-reviewed material scientific knowledge.

Or something like that :)