Ivan Seeking said:
One interesting notion that strikes me from time to time, like now, is that if String Theory [ M Theory] is correct or nearly so, the greatly anticipated theory of everything, or TOE, is not a theory of science and never can be. Rather, M theory stands as a philosophical proposition, and it appears tha tthis will always be true. As far as we know, M Theory can never be tested or qualify as a theory of science. So, this makes me wonder if this might be implicitly required somehow; perhaps due to a philosophical limitation built into science that we've missed? Anyway, not to be taken too seriously, it's just a thought that I have now and again.
Yes it seems that we have a problem with falsificability here (Popper's version), indeed an unfalsifiable theory could, still, be at least approximately true. But it's too strong to say that superstring theories cannot be tested, this remain to be seen (the theoretical work is still in progress and the hope is that at high energies they could, potentially, be 'confirmed').
In fact we have even now a clear novel prediction of string theories which is considered as potentially testable in the very near future (when the european collider will be over) namely supersymmetry. The problem is that many other theories do predict the existence of such super partners so this is not regarded as a crucial step ahead into accepting string theories as confirmed. Anyway, as enthusiasts point out well, the corroboration of supersymmetry would boost our confidence in them, that we are on the 'right track', at least that it is worth pursuing further this path as the first choice research program (this is especially important if we think at the funding of new experimental devices, very expensive, needed to, potentially, find crucial 'confirmations' of the theory).
What really put in doubt the scientific status of string theories is the fact that, apparently, they have adjustable parameters enabling them to accommodate all possible experiments, being thus basically irrefutable. For example if a version of the theory is falsified by a certain experiment (at very high energies for example) there is always room, critics say, for 'post hoc' (post fact) changes to accommodate the anomaly by adjusting those parameters.
If so then string theories are more or less in the same category with Adler's theory or Freud psychoanalysis, two well known examples of pseudo sciences indicated by Popper. However the popperians can retort that such an approach is acceptable as much as the revised version of the theory not only accommodates the existing anomalies but makes also novel predictions (potentially testable) different from those made by the earlier version of the theory (psychoanalysis or astrology for example only accommodate facts 'post hoc' without making novel, potentially testable, predictions from their new accepted premises). Remain to be seen if string theories will be able to withstand these requirements, they may why not, as of now at least there is nothing we are aware of which to impede this.
Even if the different variants would be superseded very often if the paradigm change takes place as presented above then we could still say that string theories are scientfic upon Popperian falsificationist methodology. Only the absence of novel, different predictions, could justify scientists to label it, potentially, unscientific.
But this in no way totally discredit such theoretically and experimentally stagnant programmes, and this is a real weakness of falsificationism in Popper's variant. Though they look stagnant at a certain moment such programmes could still become become progressive in the future, the history of science does offer us such examples (even seemingly degenerative programmes at a certain moment became progressive later).
Happily the mere popperian falsificationism can be improved, Lakatos presented an improved version of falsificationism which takes into account these problems, only if a program is degenerative or stagnant for very long periods of time is it totally abandoned, being considered 'falsified' (in a weak sense of course, scientists are always prepared to realize later that it is still viable). So I'd argue that string theories are scientific even now, the mere Popperian account has proved unable to make a clear distinction between science and pseudo science, its principal aim. This by no means amount to say that popperianism has to be discared, it is still a very useful methodology in the vast majority of cases, but we must be aware of its clear limitations.
