Archive for November, 2010

Snowball Earth and Complex Life

Friday, November 19th, 2010

Discussions asking whether “Snowball Earth” triggered animal evolution (see the bottom half of that page) suggest increasing evidence that the Snowball Earth hypothesis may explain an important part of why spacefaring civilizations seem rare.

photosynthetic organisms are limited by nutrients, most often nitrogen or phosphorous
…
the glaciations led to high phosphorous concentrations, which led to high productivity, which led to high oxygen in the oceans and atmosphere, which allowed for animal evolution to be triggered and thus the rise of the metazoans.

This seems quite speculative, but if true it might mean that our planet needed a snowball earth effect for complex life to evolve, but also needed that snowball earth period to be followed by hundreds of millions of years without another snowball earth period that would wipe out complex life. It’s easy to imagine that the conditions needed to produce one snowball earth effect make it very unusual for the planet to escape repeated snowball earth events for as long as it did, thus explaining more of the Fermi paradox than seemed previously possible.

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Wired for War

Monday, November 8th, 2010

Book review: Wired for War: The Robotics Revolution and Conflict in the 21st Century, by P. W. Singer.

This book covers a wide range of topics related to robotics and war. The author put a good deal of thought into what topics we ought to pay attention to, but provides few answers that will tell us how to avoid problems. The style is entertaining. That doesn’t necessarily interfere with the substance, but I have some suspicions that the style influenced the author to be a bit more superficial than he ought to be.

I’m disappointed by his three-paragraph treatment of EMP risks. He understands that EMPs could cause major problems, but he failed to find any of the ideas people have about mitigating the risk.

With some lesser-known risks, the attention he provides may be helpful at reducing the danger. For instance, he identifies overconfidence as an important cause of war, and points out that the hype often created by designers of futuristic devices such as robots can cause leaders to overestimate their military value. This ought to be repeated widely enough that leaders will be aware of the danger.

He expresses some interesting concerns about how unmanned vehicles blur the lines between soldiers in battle and innocent civilians. Is a civilian technician who is actively working on an autonomous vehicle that is about to engage in hostile action against an enemy an ‘illegal combatant’? Does a pilot walking to work in Nevada to pilot a drone that will drop bombs in Afghanistan a military target?

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Posted in Artificial Intelligence, Book Reviews, Politics | No Comments »

Leadership and Self-Deception

Thursday, November 4th, 2010

Book review: Leadership and Self-Deception: Getting out of the Box, by the Arbinger Institute.

In spite of being marketed as mainly for corporate executives, this book’s advice is important for most interactions between people. Executives have more to gain from it, but I suspect they’re somewhat less willing to believe it.

I had already learned a lot about self-deception before reading this, but this book clarifies how to recognize and correct common instances in which I’m tempted to deceive myself. More importantly, it provides a way to explain self-deception to a number of people. I had previously despaired of explaining my understanding of self-deception to people who hadn’t already sought out the ideas I’d found. Now I can point people to this book. But I still can’t summarize it in a way that would change many people’s minds.

It’s written mostly as a novel, which makes it very readable without sacrificing much substance.

Some of the books descriptions don’t sound completely right to me. They describe people as acting “inside the box” or “outside the box” with respect to another person (not the same as the standard meaning of “thinking outside the box”) as if people normally did one or the other, we I think I often act somewhere in between those two modes. Also, the term “self-betrayal”, which I’d describe as acting selfishly and rationalizing the act as selfless, should not be portrayed as if the selfishness automatically causes self-deception. If people felt a little freer to admit that they act selfishly, they’d be less tempted to deceive themselves about their motives.

The book seems a bit too rosy about the benefits of following it’s advice. For instance, the book leaves the reader to imagine that Semmelweis benefited from admitting that he had been killing patients. Other accounts of Semmelweis suggest that he suffered, and the doctors who remained in denial prospered. Maybe he would have done much better if he had understood this book and been able to adopt its style. But it’s important to remember that self-deception isn’t an accident. It happens because it has sometimes worked.

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Posted in Book Reviews, The Human Mind | No Comments »

The bacterial part of our bodies

Wednesday, November 3rd, 2010

Some quotes from Bacteria ‘R’ Us:

the vast majority — estimated by many scientists at 90 percent — of the cells in what you think of as your body are actually bacteria

researchers describe bacteria that communicate in sophisticated ways, take concerted action, influence human physiology, alter human thinking and work together to bioengineer the environment. These findings may foreshadow new medical procedures that encourage bacterial participation in human health.

Many researchers are coming to view such diseases as manifestations of imbalance in the ecology of the microbes inhabiting the human body. If further evidence bears this out, medicine is about to undergo a profound paradigm shift, and medical treatment could regularly involve kindness to microbes.

bacteria “have to have a reason to hurt you.” Surgery is just such a reason.

bacteria that have antibiotic-resistance genes advertise the fact, attracting other bacteria shopping for those genes; the latter then emit pheromones to signal their willingness to close the deal. These phenomena, Herbert Levine’s group argues, reveal a capacity for language long considered unique to humans.

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