While the West with its preoccupation with reason and rationality developed the scientistic forms sciences which ultimately results in novel technological achievements and  hence progress in material culture, the Dravidian folks appear to have developed the hermeneutic sciences which leads to developments in spiritual  or psychological technologies and hence improvements in mental and physical health.  The essential principles of this form of science  is more inclusive than the mathetically oriented scientistics and hence incorporates a conception of human rationality that is more comprehensive. There is a more inclusive concept of reason that has agitated the best of the Dravidian folks and has finally enabled them to understand Metaphysica Universalis as outlined in the 13th cent. Civajnana Botham  of Meykandar. It should be noted that Metaphysica Universalis is possible only within the notion of Hermeneutic Sciences.

The phrase " vinaiyin  n-Ingki  viLangkiya aRivin munaivan" that occurs  in one of the sutras in TolkAppiyam outlines a notion of OBJECTIVITY  that is central to the Hermeneutic Science that we are trying to articulate here. Only an individual who frees himself from prejudices of all sorts (vinai) and because of which he becomes an luminary (munaivan)  can be objective and see a thing as it is, as it discloses itself from within itself.  This is phenomenology in the true sense of the word (iyal n-eRi)  and only a person who pursues his studies with this phenomenological stance well established , can see TRUTHS  and generate a TEXT that can be authoritative (muthal n-Ul)

 Within the phenomenological attitude a person must be DETACHED and hence be NOTHING  at least during those moments he is investigating something.  Only when he keeps the possibility of NOTHINGNESS  established firmly in understanding can he remain detached, be free of prejudices and hence OBJECTIVE.

Now since objectivity as such is related to a way of Being and  hence SEEING it follows that  genuine hermeneutic sciences can be developed only by choosing UNDERSTANDING as that which ought to be investigated.  Since human understanding discloses itself as discourses of various kinds i.e. TEXTS in general, TEXTS are what ought to be procured and investigated, something we see so eminently in the body of TolkAppiyam itself. Over and above the verbal texts, the nonverbal texts such as those obtained in the Baum Test and Family Portrait Test and such other spontaneous productions of man are also taken as TEXTS , very useful for gaining a true understanding of the machinations of the human mind.
 
2.The Notion of RELIABILITY in Hermeneutic Science

With this clarification it is possible now to explain the meaning of RELIABITY as it obtains in the hermeneutic sciences.  The Hermeneutic Scientist in order to be truly OBJECTIVE , has to be NOTHING in terms of prejudices, at least during those precious moments at which he is an investigator. He would then obtain a TEXT without tempering with the productive processes, abstain from   interference and such direct or indirect manipulations that would serve to project his OWN ideas rather than that of the subject being investigated. The investigator is free to create a context of a kind for otherwise TEXTS of  useful kind cannot be obtained. Having created the necessary context in which the subject produces, he should then withdraw himself from it,  be ABSENT, be NOTHING subsequent to that so that subjects are FREE  to respond in a manner they see fit.  The responding here is actually that of EXPRESSING himself so that what he is himself gets a textual manifestation. In Hermeneutic    Sciences, we do not obtain data on the basis experimentation which are always manipulations of the subjects  to test whether  a particular hypothesis the experimenter has in mind, holds or not.

The focus on analyzing   expressions as such also means there are no INSTRUMENTS  in the hermeneutic sciences and hence concerns as to whether a particular instrument is reliable or not, REALIABILTY being here something measurable. It  is  understood that MAN IS NOT THE MEASURE of everything and  hence acknowledging the possibility of TRUTHS outside and above instrumental interventions. In Hermeneutic Sciences we investigate only TEXTS and they are RELIABLE only when they are obtained as spontaneous productions of the subjects,  expressions  emerging  out of the subjects themselves and from within without being subjected to any manipulations. The personality of the investigator must not be present either directly or indirectly in a manner that would affect the productive or expressive processes.

3.The Notion of VALIDITY

Having clarified the notion of RELIABILITY thus now we have to attend to the important notion of   VALIDITY.  Certainly the TEXT in relation to the way it is obtained is irrelevant to the notion of validity. For validity pertains to JUDGEMENT and hence to the notion of TRUTH.  The attitude of standing detached in the analysis of TEXTS is also relevant here for it is within this attidute that TRUTHS can be sighted.

Now every TEXT, because it points to something beyond and above itself,  has DUAL STRUCTURE, the Surface Structure (S.S) and Deep Structure (D.S ) .  A preunderstanding of a text enables only a partial understanding of it. It simultaneously points to a subjective condition of being IGNORANT pertaining to the meaning of the text as a whole. In other words  while we have only a partial understanding of a text, there is no translucency but rather an opacity in the relationship between the investigator and the text. The subjectivity of the investigator is EXPOSED as ignorant and hence necessitating the exercise of   interpretive maneuvers to destroy it.  When a person notes  certain  features of the S.S and and remains ignorant of them, he seeks to locate some elements in the D.S that are causally related to them. Since the causal presence comes along with simultaneity, the causation is not physical but rather AGENTIVE.  The D.S elements agentively determine the observable features of the S.S. and when a person successfully locates these agentive causes, he UNDERSTANDS the text.  Such an understanding when gets articulated generates a text about a text for which reason we call it a METATEXT (  The Tamil linguists call it CeyyuL).   Since there is the possibility of making mistakes, of being in error and so forth, the question of the VALIDITY and the TRUTH of such claims emerge here.  The interpretation here is in fact  ontopretations, a going beyond the surface features  and reaching  the deep structure elements that in fact constitute them.  The gaze goes beyond the surface and reaches the hidden, the concealed but which are in the texts themselves, in situ.  And when the right D.S. structure is sighted then it can also be SEEN by others. This possibility of making others see what one succeeds in seeing ensures that what is seen is objectively there in the TEXT itself and not simply a construction an imagination, a subjective fancy and what not.

Now since seeing what are there though concealed somewhat constitutes seeing TRUTH it foollows that what is seen thus also VALID.

Reference

Loganathan,K. Metaphysica Universalis of Meykandar  (Available in this Home Page under classical texts)