JOHN McCARTHY IS an optimist. Yet the field McCarthy is most commonly associated with, artificial intelligence, has made little progress since 1956, when he convened the first Dartmouth conference.
"I've been working on logical AI since 1958," he says, "and I've done some I think good work (and other people also), but still we don't have human-level intelligence yet. I can't predict any definite date at which it will be achieved, even though Ray Kurzweil is eager to say it will happen by 2029. If I live to be 102 and am still capable of laughing I expect to laugh at him then."
He sees no evidence, either, for that science fiction staple the Singularity. Even so, he remains optimistic. He points to genetics as an example. Mendel laid the foundations in 1865, but the genetic code wasn't cracked until the 1960s, And even now, "Still we don't know how genetics controls the shape of an animal. So that's taken even longer than I have so far. Hard scientific problems are hard."
McCarthy's less formal interests are wide-ranging: human expansion beyond the earth, the search for extraterrestrial intelligence and, the topic he most wants to talk about, sustainability.
Partly, he attributes this to his background. "I was brought up as a communist," he says. As a child, he read a translation of a Russian's children's primer, 100,0000 Whys, which, he says, "was enormously optimistic about technology". (McCarthy became a liberal in 1952, then, in 1972, a Republican). Attending local colloquia on the search for extraterrestrial intelligence has sparked thoughts about what kind of intelligence would likely exist.
Take, for example, the difference between octopus eyes and vertebrate eyes, which do the same job but are completely unrelated genetically. "It says the world presents the same kinds of problems to animals and plants, and sometimes they solve them, and even things with quite different backgrounds may come up with the same solution." Applying that to SETI, he imagines that the networks of neuron in which intelligence is implemented on earth might exist in other solar systems where intelligence evolved differently – though that intelligence would still be able to do arithmetic and know mathematics. Sustainability occupies many pages of his Web site. ("Why," he asks parenthetically, "won't Who's Who let you list your Web address?") The gist: "Doom-saying is mistaken, and material progress of the kind we've had in the past is sustainable for the foreseeable future, contrary to public opinion."
McCarthy's site assembles evidence to back up his contention on a range of topics: energy, food supply, population, water, forests, wood supply, pollution and biodiversity. "My argument that these menaces will be overcome does not depend on any futuristic technology. It depends on the technology we already have." Although, he adds, "Naturally there will be futuristic technology."
This sort of optimism is at the very least unfashionable at the moment, but McCarthy believes the evidence supports his point of view, noting that the average time frame for disaster predictions is two years. "I would say that the area where I'm weakest is erosion, because the estimates of the rate of loss of topsoil by erosion that I've found differ by a factor of 100 from each other." Overall, he says, "The key thing that gives rise to confidence is that plenty of energy is available, most specifically nuclear energy, but solar probably will also work."
McCarthy, who for a time early in his life read a lot of science fiction, is, however, willing to consider solutions that environmentalists generally would hate. For example, when William Calvin predicted in Atlantic Monthly in 1998 that the Gulf Stream would stop, he asked his students to calculate the cost of covering Western Europe with transparent plastic, making it a giant greenhouse.
"Calvin and the doomsters in general do not write counter-measures to the disasters they are predicting," he says. "There is an actual prejudice against global engineering on the grounds of interfering with nature."
Overall, he says, "I like to think in terms of opportunities rather than inevitabilities. So technology will offer that opportunity. Who will take it is another question." µ
This could be it:
http://www.theatlantic.com/past/docs/issues/98jan/climate.htm
He's a good read. And a lot of what he says is logical to me. His point on extra terrestrial intelligence seems sound. It basically states that time is the big factor. We've only been able to transmit radio signals for app. 1 century (where's my wiki?). Over the next century, our technology will/should improve exponentially, if we follow current trends. And it's likely that we will do this, barring an unforeseen global setback. It's hard to predict where we will be in 1,000 years. But it does seem likely that we will look upon our current selves less than the current 'we' look upon cavemen. 2,000 years from now, your guess is as good as mine... Now if you look at this 2,100 years of elapsed technology and plot it against the lifetime of the universe, it barely registers as the slightest blip. So not only are we having to find the 'needle in the haystack', we have to find a needle that is constantly moving randomly around a 3D space (i.e. solar systems). 

You have to ask yourselves; Given a civilization has 10,000 years of technological development (still a blip on the timeline) and allow them to receive our 'basic' radio frequency signals, how likely are they to respond or even be interested in responding? Without reading the droves of responses based on Star Trek: First Contact, I will say that I agree with those odds. But not as predicted in the movie. I think that finding outer-worldly civilizations will be greatly improved, if and when we can traverse the depths of space quickly. If anything, by the fact that our travels may leave behind certain energy signatures (tire tracks, if you will), we will notice or get noticed. 

As for A.I. the timeline is uncertain as are the requirements for reaching it. Ray does a good job of tackling both. And I'd recommend reading him.
William Calvin predicted in Atlantic Monthly in 1998 - Wherez the LinQ?? InQ foolin its readers with blue colored text instead of hyperlinks :P