Showing posts with label Arizona. Show all posts
Showing posts with label Arizona. Show all posts

Thursday, 18 September 2014

Master Critical Thinking

How To Develop Your Critical Thinking Skills


By


subconscious mind What are critical thinking skills? They are the habits of thought that you cultivate for better decisions on what to believe and what to do. Critical thought is not about being able to argue well. That kind of thinking can be a trap. Unfortunately, some very intelligent people think that way, seeking only to justify the beliefs they already have. That is very limited thinking.



Ask psychologists, philosophers, and brain scientists what critical thinking is, and you’ll get many definitions. However, all of them seem to agree that it includes challenging and analyzing our own motivations, thought processes and conclusions. Here is a basic definition:


Reasonable and reflective thinking focused on deciding what to believe and/or how to act.”


Reasonable shouldn’t be confused with logical, since many of the most unreasonable ideas result logically from a chosen set of premises and assumptions. A set of premises which include a flat Earth, for example, can lead to the perfectly logical conclusion that a boat will fall off the edge of the planet if it goes too close. Logic is a systematic way to derive conclusions from premises, but the premises themselves may be right or wrong.


Guidelines for Critical Thinking

Guidelines for Critical Thinking (Photo credit: mrobisonabc)



Being reasonable then, means allowing for the possibility that reality may not match our premises. Being reasonable means observing, gathering evidence, and using inductive reasoning (all dogs I see have four legs, so dogs must normally have four legs). On the other hand, logic is limited to deductive reasoning, and one bad premise can taint all deductions that come from it. It is reasonable, therefore, to challenge not just our logic, but the premises it is based on.


To be reflective, is to ask questions like, “How could I be wrong here? What assumptions am I making and are they correct? Are there other explanations that may be better?


Suppose on a hot humid day, you think, “Humidity makes the air feel warmer, and it is normally more humid in Montana than in Arizona, so if the temperature is the same in both places, it will normally feel warmer in Montana.” Unassailable logic, but a wrong conclusion, as I and anyone who has lived in both places in winter can tell you. Humid air actually feels warmer when it’s hot and cooler when it’s cold.


To avoid errors like this, you ask if it’s true that humidity makes air feel warmer. A hot day’s experience says yes, but when you look for possible errors you note the hidden assumption that “it’s true at any temperature.” You challenge that assumption,and remember that the hot feeling is partly because your sweat can’t evaporate as fast in humid air, so your body can’t cool itself as well. Reflecting on that, you realize it wouldn’t matter as much when it’s cold, because you sweat less.


Cultivate Your Critical Thinking Skills


You may already have enough knowledge to correct the error, but if not, a bit of critical thought would at least point out the need to gather more information. You can see in this example the kind of mind set you need as a critical thinker. What else can you do to develop critical thinking skills? There are specific exercises and practices for that. Here are three of them.


Evidence


Make it a habit to ask for evidence. That might mean simply asking “where did you read that?” or “Was that speculation, or did they actually do a test?” Be prepared to provide evidence for your own claims as well. We don’t carry our sources with us, of course, but you should be able to get a sense whether there really is some basis for a claim or belief.


Source


Because we don’t carry evidence around with us, we all accept many things said at face value, at least for the sake of discussion. Otherwise our conversations would be more like interrogations, and probably very short. However, we can consider the sources of information and evidence. We can ask if this person usually remembers the facts correctly. We can consider if the source they refer to is reliable.


Motivations


What we believe, what others believe, and what evidence is considered by anyone, is in part a function of motivations. Because of this, a magazine might be entirely biased in it’s reporting, yet have all of their facts perfectly verified. Of course, you should ask yourself if there is enough of a motivation for outright lying, but this isn’t as common as many people think. A more important part of you critical thinking skills is to ask why these certain facts may have been reported (what bias is likely), and what facts are being ignored or passed over.



Copyright Steve Gillman. For six more specific Critical Thinking Skills, and to get the Brainpower Newsletter and other free gifts, visit: http://ift.tt/1cZJ8kt






The post Master Critical Thinking appeared first on Robert JR Graham.


Sunday, 17 August 2014

Master Critical Thinking

How To Develop Your Critical Thinking Skills


By


subconscious mind What are critical thinking skills? They are the habits of thought that you cultivate for better decisions on what to believe and what to do. Critical thought is not about being able to argue well. That kind of thinking can be a trap. Unfortunately, some very intelligent people think that way, seeking only to justify the beliefs they already have. That is very limited thinking.



Ask psychologists, philosophers, and brain scientists what critical thinking is, and you’ll get many definitions. However, all of them seem to agree that it includes challenging and analyzing our own motivations, thought processes and conclusions. Here is a basic definition:


Reasonable and reflective thinking focused on deciding what to believe and/or how to act.”


Reasonable shouldn’t be confused with logical, since many of the most unreasonable ideas result logically from a chosen set of premises and assumptions. A set of premises which include a flat Earth, for example, can lead to the perfectly logical conclusion that a boat will fall off the edge of the planet if it goes too close. Logic is a systematic way to derive conclusions from premises, but the premises themselves may be right or wrong.


Guidelines for Critical Thinking

Guidelines for Critical Thinking (Photo credit: mrobisonabc)



Being reasonable then, means allowing for the possibility that reality may not match our premises. Being reasonable means observing, gathering evidence, and using inductive reasoning (all dogs I see have four legs, so dogs must normally have four legs). On the other hand, logic is limited to deductive reasoning, and one bad premise can taint all deductions that come from it. It is reasonable, therefore, to challenge not just our logic, but the premises it is based on.


To be reflective, is to ask questions like, “How could I be wrong here? What assumptions am I making and are they correct? Are there other explanations that may be better?


Suppose on a hot humid day, you think, “Humidity makes the air feel warmer, and it is normally more humid in Montana than in Arizona, so if the temperature is the same in both places, it will normally feel warmer in Montana.” Unassailable logic, but a wrong conclusion, as I and anyone who has lived in both places in winter can tell you. Humid air actually feels warmer when it’s hot and cooler when it’s cold.


To avoid errors like this, you ask if it’s true that humidity makes air feel warmer. A hot day’s experience says yes, but when you look for possible errors you note the hidden assumption that “it’s true at any temperature.” You challenge that assumption,and remember that the hot feeling is partly because your sweat can’t evaporate as fast in humid air, so your body can’t cool itself as well. Reflecting on that, you realize it wouldn’t matter as much when it’s cold, because you sweat less.


Cultivate Your Critical Thinking Skills


You may already have enough knowledge to correct the error, but if not, a bit of critical thought would at least point out the need to gather more information. You can see in this example the kind of mind set you need as a critical thinker. What else can you do to develop critical thinking skills? There are specific exercises and practices for that. Here are three of them.


Evidence


Make it a habit to ask for evidence. That might mean simply asking “where did you read that?” or “Was that speculation, or did they actually do a test?” Be prepared to provide evidence for your own claims as well. We don’t carry our sources with us, of course, but you should be able to get a sense whether there really is some basis for a claim or belief.


Source


Because we don’t carry evidence around with us, we all accept many things said at face value, at least for the sake of discussion. Otherwise our conversations would be more like interrogations, and probably very short. However, we can consider the sources of information and evidence. We can ask if this person usually remembers the facts correctly. We can consider if the source they refer to is reliable.


Motivations


What we believe, what others believe, and what evidence is considered by anyone, is in part a function of motivations. Because of this, a magazine might be entirely biased in it’s reporting, yet have all of their facts perfectly verified. Of course, you should ask yourself if there is enough of a motivation for outright lying, but this isn’t as common as many people think. A more important part of you critical thinking skills is to ask why these certain facts may have been reported (what bias is likely), and what facts are being ignored or passed over.



Copyright Steve Gillman. For six more specific Critical Thinking Skills, and to get the Brainpower Newsletter and other free gifts, visit: http://ift.tt/1cZJ8kt






The post Master Critical Thinking appeared first on Robert JR Graham.


Saturday, 7 June 2014

Use Rain Power and Solar Power Together!




by: Marcus Bicknell








page59image 300x239 Use Rain Power and Solar Power Together! The rainwater harvesting industry is constantly looking for different ways of making rainwater harvesting more economical and practical. Rainwater harvesting means you can use between 30% and 50% less on mains water consumption, and since we are all now under strong government pressure to do this. The Code for Sustainable Homes recommends rainwater harvesting for its higher target levels (maximum of 80 litres per day per person) and new Building Reg Part G 17K coming in April 2010 will, mean that, for the first time, water consumption limits will be a legal requirement in new buildings.








Rainwater harvesting does, however, in most circumstances use an electric pump to take the stored rainwater to where it is needed, and this pump needs power. Steps have already been taken to reduce this pump energy use. There are now specially-designed gravity feed systems whereby a rainwater header tank is only refilled when empty rather than every time water is drawn. This avoids the pump hunting, reduces pump activity considerably and, therefore, reduces energy use. The next logical step has been to use solar energy to power the pump.








A solar panel the size of a small car windscreen can power a gravity-feed rainwater management system. The solar panel, in combination with a submersible 12 volt pump in the main storage tank and a battery ensure rainwater can be pumped to the rainwater header tank without any use of mains electricity. The control mechanism of the system and the pump are both powered by the battery that is kept topped up by solar power in daylight hours. Even on a cloudy day, tests show that the most up-to-date solar panels can give six times the charge necessary to run a rainwater harvesting system in a typical family home. In the unlikely event of the panel not providing enough charge to the battery, mains electricity is used as backup. Furthermore, unlike normal chargers, the standby mode of the mains charger takes no current at all, not even a trickle.








So in such a system, the powerful mains-electric pump is replaced by a small 12 volt pump which pumps to 8-10 metres high, enough to feed a header tank on a two story house. One or more relay pumps, with supplemental solar panels, can be added for taller buildings. It should be noted that this system does not provide enough pressure for garden sprinkling but gravity fed irrigation is fine.








For quite a while, solar pump kits have been available allowing rainwater to be moved without the need for mains electricity and without having to turn on and off manually. Water can be moved, for example, from a low level collecting tank in the garden (or even at the end of a polytunnel or greenhouse) to a storage tank at a higher level. The applications are numerous in allotments, equestrian properties, market gardens and for water features. These kits can supply a drip feed watering system through a header tank (so that water is available for gravity feed at any time, even through a time switch). In more sophisticated kits, when the float switch detects water, it starts pumping, then when the header tank is full, it turns the pump off.








Using solar energy to power the pump is a big step forward in making rainwater harvesting an attractive sustainable proposition by saving water while not using extra power to do so.








Source