|MadSci Network: General Biology|
Is thinking a property of all life? If so, do plants and animals think? At first thought, I’d say animals think, but plants don’t. But the question is interesting. According to my dictionary, to think is “to form or have in the mind; conceive...” By this definition, you would need a mind to think. For me, thinking is done by a brain, using neurons, to process information. Thinking, for example, is used when a response must be chosen from a number of alternatives. A simple reflex would not be thinking. People have minds and they think. Early philosophers discounted the ability of animals to think. Descartes, for example, considered animals to be just mechanisms. Now many people think that animals can think. Chimpanzees have some ability to communicate, to solve problems, and to recognize themselves in a mirror, so they must, in my opinion, be thinking. Some say that they are just mimicking and responding to their trainers, but as I surf around, I get the feeling that chimps think. Jane Goodall says that chimps watch pretty sunsets. They must be thinking of something. Of course, a chimp’s mind is not as powerful as ours, so a chimp’s thoughts would be proportionally less deep (and nonverbal). If animal thought is a matter of degree, then dogs and cats have some ability to think, albeit less than people or monkeys. Many pet owners ascribe thought and awareness to their pets. There is a danger of “anthropomorphizing”, or giving human qualities to animals. I know some pet owners who seem to give their pets too much credit, but my cat seems to be happy when I get home. She knows she’ll get something to eat, I think she must be thinking about it. I hope I’m not anthropomorphizing. Cats and dogs can solve simple problems. I think that thinking is what they’re doing between encountering a problem and finding the solution. See the intelligent cat: http://www.catsinternational.org/articles/training/the_intelligent_cat.html Here are some articles about “do animals think”: http://www.guardian.co.uk/hunt/Story/0,2763,861968,00.html http://www.findarticles.com/cf_0/m1175/6_32/56883557/p1/article.jhtml http://www.pbs.org/thinktank/transcript802.html What about lower animals? Mice? They need to make decisions as well as they can. Thinking would be what they’re doing between encountering a problem and finding the solution. I don’t think they think very deeply, but they may be thinking their mouse thoughts. Reptiles? The mammalian brain has a neocortex, while the brain of reptiles and lower are dominated by the brain stem and cerebellum. A mouse was once considered to be a mental giant compared to a reptile. Then reptiles and fish must think on an even lower level. But snakes (and birds) seem to have more smarts now than we once thought: http://www.lasuerte.org/omesnakes.htm A fly has a brain of about 250,000 neurons. It can learn has memory. A round worm’s brain is only 302 neurons, and even the worm exhibits behavior and is capable of rudimentary learning. It’s hard to say what a worm or a fly is thinking, but I continue to be surprised at the complexity you can get from a small number of components. Plants and single cell organisms have no brains. They can react to their environment but I don’t think they are thinking. One very “zen” idea is that consciousness extends from us all the way down to the lower animals and even down to blocks and stones, which have the lowest consciousness. (Search panpsychism.) Years ago, I was discussing this with Milton Rothman, and he pointed out an article by Andrew A. Cochran in the Foundations of Physics, Vol. 1, p235 (1971). The article is about “proton consciousness”, in which consciousness is extended all the way to subatomic particles! I don’t agree with everything in the article, but it is in the literature. If consciousness implies thinking, or if thinking can be extended similarly, then everything thinks. That’s a bit far out for my tastes, but I included it to show some of the weird thoughts that can come from thinking about this question. Mike Conrad.
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