Enthusiasm of early inventors. AI hype
Things that used to be considered intelligent: IQ tests, playing chess
Alan Turing invented the computer as universal machine that emulates a mathematician.
He and his whole generation of technological enthusiasts where convinced that this type of machine would eventually become intelligent once it became complex enough to match the complexity of the human brain.
Quality: not IQ tests, no chess playing, but learning and reacting to unanticipated situations.
What happened with Cyc? All these ambitious AI programs? Where are all these expert systems?
Penrose thinks that there are physical laws involved in the human mind that are not Turing computable. The question is what these effects might be, and Penrose himself has some ideas about what these might be. All the physicists I've talked to have strongly rejected his argument.
I can only tell from my own experience - and I've worked with computers a lot: they don't get more intelligent if they get more complex. Just on the contrary. The more complex the computers are, the more can go wrong, and the more stupid they turn out. And the worst is if compute pretend to be intelligent while they really aren't: just look at the "intelligent" paper clip in Microsoft Office.