In Science: Conjectures and Refutations, Sir Karl Popper wrote:
These considerations led me in the winter of 1919-20 to conclusions, which I may now reformulate as follows.
(1) It is easy to obtain confirmations, or verifications, for nearly every theory-if we look for confirmations.
(2) Confirmations should count only if they are the result of risky predictions; that is to say, if, unenlightened by the theory in question, we should have expected an event which was incompatible with the theory-an event which would have refuted the theory.
(3) Every "good" scientific theory is a prohibition: it forbids certain things to happen. The more a theory forbids, the better it is.
(4) A theory, which is not refutable by any conceivable event, is nonscientific. Irrefutability is not a virtue of theory (as people often think) but a vice.
(5) Every genuine test of a theory is an attempt to falsify it, or to refute it. Testability is falsifiability; but there are degrees of testability; some theories are more testable, more exposed to refutation, than others; they take, as it were, greater risks.
(6) Confirming evidence should not count except when it is the result of a genuine test of the theory; and this means that it can be presented as a serious but unsuccessful attempt to falsify the theory. (I now speak in such cases of “corroborating evidence.")
(7) Some genuinely testable theories, when found to be false, are still upheld by their admirers-for example by introducing ad hoc some auxiliary assumption, or by re-interpreting theory ad hoc in such a way that it escapes refutation. Such a procedure is always possible, but it rescues the theory from refutation only at the price of destroying, or at least lowering, its scientific status. (I later described such a rescuing operation as a "conventionalist twist" or a "conventionalist stratagem.")
One can sum up all this by saying that the criterion of the scientific status of a theory is its falsifiability, or refutability, or testability.
First, Sir Karl Popper recognized the value of metaphysical theory which cannot be refuted or falsify by mere empirical observation. In the same article, he wrote,” I thus felt that if a theory is found to be non-scientific, or "metaphysical" (as we might say), it is not thereby found to be unimportant, or insignificant, or "meaningless," or "nonsensical." it cannot claim to be backed by empirical evidence in the scientific sense-although it may easily be, in some genetic sense, the "result of observation."
According to him, even though metaphysics cannot be tested, it does not weight down its significance. From this point of view, there is no problem between his theory of falsification and theistic claim of the existent of God.
But what troubled me were the attempts by some anti-theists who argue that as long as a theory (be it metaphysics or physics) is not scientific, it cannot be in consideration at all.
To this charge, I may want to remind the incompetence of this principle in its nature cannot be a measurement use on metaphysics.
The principle of falsification can only be applied on theories of operational sciences; due to its limitation of not able to withstand itself of being refuted and falsified by its very own principle, if granted its application in metaphysics.
To its best, this principle can be consider as a meta-statement or meta-theory, which elevates itself beyond its very own nature in order to preserve its advantage of applying itself onto physical science, operational science or origin science.
Philosophically, to the materialists, this theory cannot be refuted or falsified, thus this theory cannot be consider as scientific as well. And if you realized, my previous sentence, which had falsify the principle of falsification, has granted the principle the status of being scientific, according to its own theory.
Yes, it is scientific, but scientifically refuted, if you like. (In another words, this principle is proven wrong by observation and examination, therefore it cannot be hold as true/ applicable, in its metaphysical nature).
Can you see its incompetency now?
This principle might work on drawing a line between science and pseudo-science, but only in physical reality. It must not touch metaphysics or pure philosophy.
This principle failed, if it ventured beyond the realm of physics. It is falsifiable and, in fact, falsified as demonstrated above, with its own principle. Which means, when it works, it kills itself.
This principle can only be more like a reminder to scientist in every field to constantly examine their findings and try to refute them in genuine and honest ways, so that those irrefutable theories might stand as real science.
Metaphysics is a science, as I see it. And its scientific status is definitely not confined by this falsification principle. It cannot categorize metaphysic as non-scientific and physics as scientific as claimed by some anti-theists.
Norman Geisler, BECA
Karl Popper, Science: Conjectures and Refutations (http://cla.calpoly.edu/~fotoole/321.1/popper.html)
p/s: I suppose you have a certain depth of understanding in the above entry if u are reading this. Please criticize. Thank you.
p/s 2: Now only i noticed that Sir Karl Popper categorized his Falsification theorem into 7 points/stages.... same like my Supreme Systematic Apologetics.... hahahaha *vain laughter*