Full Idea
The Turing test is too tough, because something doesn't have to be smart enough to outwit a human (or even have language) to have mentality or intelligence.
Gist of Idea
A machine with a mind might still fail the Turing Test
Source
Jaegwon Kim (Philosophy of Mind [1996], p. 97)
Book Reference
Kim,Jaegwon: 'Philosophy of Mind' [Westview 1998], p.97
A Reaction
Presumably an alien with an IQ of 580 would also fail the Turing test. Indeed people of normal ability, but from a very different culture, might also fail. However, most of us would pass it.