Though it does not affect the main point (that the 'key tenet' is implicit, not explicit, in TLP) there is an error of substance right at the end of yesterday's post (an error I've slipped into before). >In the TLP, W was bound to the view that what his propositions show is “senseless” even though it is “the truth”: hence ‘6.54’.> This should have read: "In the TLP, W was bound to the view that what his propositions say is “senseless” even though what they show is “the truth”: hence ‘6.54’." What they say is "senseless" when judged by the 'criterion of sense and nonsense' that TLP adopts viz. that only the propns of the natural sciences have sense. But what they show is "the truth" - and this need not be "senseless" according to TLP's 'criterion of sense', as this criterion applies to what propns say not what theyshow. Though it was referred to as a 'doctrine of sense and nonsense', and it is a doctrine, it might be better termed a 'criterion of sense and nonsense'. It was this criterion that was taken by the Logical Positivists as central to the TLP, rather than the 'key tenet' and the doctrine of 'what can be shown not said', as this criterion suited their own purposes. As a matter of the history of ideas, this 'criterion' is far from original to W or the Logical Positivists - it can be extracted, for example, from the philosophy of Hume. For Popper, neither the 'key tenet' and the saying/showing distinction are very original either [the idea of what is inexpressible is almost as old as any philosophy of 'what is expressible', and that is v old indeed]. (Indeed, my guess is that's W originality appeared much more significant in Anglo-American circles than in the Vienna Circle, or to those au fait with fin-de-siecle Viennese thought.) However, the TLP's view that language has sense because it is isomorphic with reality is an idea given a distinctive and original treatment - and it may even be an original idea. Popper describes this idea as one that might be regarded as a cosmological thesis, albeit a "crude" one.It is not only "crude" but false; and based on a mistaken, 'logicist' philosophy of language - here Popper and the later Wittgenstein might agree. Donal Europa