I'd say that Interlingua is "scientific" in the sense that it was constructed on basis of scientific research. Look at it this way: imagine that sometime in late 1949 IALA had decided to junk the idea of an IAL, and simply publish their research. Essentially, they'd have produced a work of philology: a scholarly survey of neo-Latin and pan-European Wanderwoerter. Now, suppose the heading for each entry was "standardised" form of the different variants - would that be science, linguistic engineering, or pseudo-science? Well, to say that you can model a standard form according to objective methodology is neither scientific not unscientific, although it is compatible with scientific activity. However it is legitimate philology to note that LA "causa" has mutated into two separate words (in terms of form/meaning) in the modern european languages, which can be modelled as CAUSA and COSA. (Interestingly enough, De "Sache" has shadowed the Latin development, from 'cause/legal case' to 'thing' - illustrating the convergence that underlies the idea of SAE.) It's also philology to note that in many cases the modern-day forms have completely lost some original phonetic features so that the "theoretical ancestor" may not be the actual etymological form. That's something the prototyping methodology could show you. The Interlingua-English Dictionary, as published, is not a scientific work, but it was based on scientific work, IMO. I don't make the same claims to Ia's grammar, however. It seems fairly impressionistic, although Gode & Co. tried to follow, in spirit, the same approach they'd taken to vocabulary. Cheers, Chris