The attendants of ‘cafés philo’ in Paris - I can only assume - offer a representative sample of how people think, at least there. I can't help noticing some disturbingly popular ‘memes’ (I don’t like the word but admit it is useful, especially the connotation that it refers to ideas whose value lies in their ability to survive rather than in their veracity).

Some examples: that reality does not exist, and perhaps only language does; that psychoanalysis is something much more than just therapy; that Myth has an inherent value or nobility that Science lacks.

One version of that last one crops up all over the place. The idea is that because theories (scientific, philosophic, mathematic) are abandoned and replaced over time, they are hence no more than expedient fashions, tools of the powerful, one manipulation followed by another, etcetera. Reason therefore has no more claim to universality than Myth; actually it is inferior, because Myth remains a constant source of meaning through our history; etcetera.

Thomas Kuhn is the godfather of all this. For a good short refutation of his thesis, see Sokal's Fashionable Nonsense. Essentially: (a) the supposed 'paradigm' of one theory does not overwhelm the senses enough to prevent scientists from contemplating alternatives (otherwise theories wouldn't change at all), (b) natural science makes dramatically more concrete predictions than does social science, e.g. Kuhn's theory itself, and (c) the idea is self-defeating, as are all theories of relativism: are we supposed to take Kuhn as the exception to his rule? Either way, he undoes himself. But in Kuhn's defence, I don't think he intended to unleash the kind of unbridled relativism that followed. I suppose he was just making a comment on the inefficiencies inherent in scientific method.

When a theory is abandoned, it is (possibly without exception) because a better approximation of truth has invalidated it, or shown it to be a transitional stage only in our understanding of truth. So Humourism giving way to the Germ Theory of Disease does not represent a change in human tastes or dominant elites. It is a qualitative leap in the apprehension - through reason - of Nature.

The constancy of Myth on the other hand is due either to its inherent irrefutability, its protection from refutation by taboo and violence (intellectual and bodily), or its just being an entertaining or edifying yarn worth repeating to the kids.