I'll happily step out of the way once someone simply tells me what it is you're trying to accomplish. Until you can actually define it, you can't do "it".

yes, a glib response, but think about it: we define an intelligence test for humans, which by definition is an artificial construct. If we then get a computer to do well on the test we haven't proved it's on par with human intelligence, just that both meet some of the markers that the test makers are using as rough proxies for human intelligence. Maybe this helps signal or judge if AI is a useful tool for specific problems, but it doesn't mean AGI

As for IQ tests and the like, to the extent they are "scientific" they are designed based on empirical observations of humans. It is not designed to measure the intelligence of a statistical system containing a compressed version of the internet.