by Dr Barry R. Clarke
There are many examples in the history of the Shakespeare authorship question of theories relating to the supernatural. They usually run in close association with the ideas of codes, ciphers, and secret sects, but although unfamiliar to common experience, is an esoteric theory necessarily a false theory?
First of all, the distinction between the scientific and the non-scientific is not the same as that between the rational and the non-rational. Certain mystical views can be perfectly coherent in that their conspiracy of ideas remain free from contradiction (and I know some highly intelligent people who hold such ideas). I think a more accurate distinction, and it is one that was pointed out by Karl Popper in Logik der Forschung (1935) , is that between what is testable and what is not. In other words, in order to corroborate a theory, there needs to be a way of singling it out from the rest. It seems to me to be a characteristic of an esoteric theory that its consequences cannot easily be subjected to a critical test. However, this does not mean that its ideas are necessarily false because it is always possible that some fact might later appear in support of the view. (For example, the idea that at some time in the future the earth might be visited by aliens always remains an open possibility.)
A further point worth advertising is that both scientific and mystical views are conjectural in character. There is no such thing as inductive reasoning from experience. Although the sense data that are given to us arise from a place external to our minds, in the process of it passing through our sensory apparatus and then our understanding, it is continually subjected by the imagination to possible ways of making sense of it. In other words, as far as our sense data are concerned, the process of organisation is an iterative process of posit and test, not an extraction of information. We keep trying different ideas until we find one that works. General relativity is a good example of the conjectural nature of scientific theory because until it found corroboration (in the advance of the perihelion of Mercury and the displacement of star positions as light bent around the Sun) the idea of ‘curved space’ certainly seemed mystical. So not only can esoteric ideas be rational, but scientific theorising begins with the intuitive and non-rational!
So for me, it is perfectly rational to hold esoteric or non-scientific views. However, in matters concerning the Shakespeare authorship question, I have elected to follow the more painful path of trying to establish what is scientific and testable, if only because any knowledge that anyone obtains in this way is something we can (hopefully) all agree on!
 Karl Popper, Logik der Forschung (1935), translated as The Logic of Scientific Discovery (Routledge, 2002). See in particular ‘Falsifiability as a criterion of demarcation’, pp.17-18 .