Theories, Laws & Reasoning - Introduction to Biology - 2.2

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• published: 21 May 2014
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Let's say that you've created an amazing hypothesis. You tested it tens, hundreds, and if you're really lonely and have nothing better to do with your life, a hundred times. Each one of those times you've tested your hypothesis it came out correct. You've even had multiple people test the hypothesis... And it came out right. If enough evidence shows that you're hypothesis is correct, you might have something special. You may have a scientific theory. I'm Jack Jenkins, this is introduction to biology and today we are talking about theories, reasonings and laws. A scientific theory is a general explanation of a phenomena. A phenomena is an observation that has to exist, such as the sun. It's different than an observation that doesn't exist, such as my friends tonny and cj. An example of a scientific theory is the phlogiston theory. The phlogiston theory states that there is a fire-like element called phlogiston. The theory of phlogiston was created to explain the phenomena of explosions. Nows the time to say, and I emphasize this, that just because something is a theory or a hypothesis doesn't mean it's true. The theory of phlogiston is false. Why would there be an element that makes things explode? Everyone knows combustions are caused by homework. Sorry... I gotta input one meme per video, it's the rule... Set by me. So how are scientific theories formed. Well, unlike shopping for t-shirts, scientific theories come from reasoning. And in the science world, there are two types of reasoning, deductive and inductive reasoning. Deductive reasoning is determining an outcome based on premises. Premises are statements or ideas that are amused or generally accepted to be true. For example, the premise that humans generally have to legs or that jack is an amazingly hot. Yeah baby! Look at me! Once you have some premises, you will be able to derive an outcome from them. Example: Humans are mortal. I am a human. Therefore, I am mortal. Deductive reasoning is nicked named "top-down reasoning" because you are deriving a specific idea from broader ones. Inductive reasoning is starting from a particular observation and going into a general scope. Which is, of course, the opposite of deductive reasoning. Usually inductive reasoning starts off with specific data and reaching a general idea based off of it. Example: I have a bag of marbles. I pull one out and it's red. The next one is blue. The third one is red. Using inductive reasoning, the next one is going to be blue. Inductive reasoning is nicked named "bottoms-up reasoning" Because you are deriving a general conclusion based on specific information. There are pro's and cons to both of them. The good thing about deductive reasoning is that the outcome will be true. However, it may not always be true. Example: All birds fly. Finches are a bird. Therefore, finches fly. This may not always be true though. If the something happens to the finch, such as death, then that birdy ain't gonna be flying no mo! Another problem is that the premise may be false. For instance, not all birds fly. Penguins are birds and they don't fly. Inductive reasoning isn't any better. We can gather true data and draw a crappy conclusion from that data. Example: Herald has glasses. Herald is a nerd therefore, nerds have glasses. That's so not true. I didn't have glasses in junior high and I was a total nerd. Just remember, no matter what form of reasoning you use, you may not always draw a true conclusion. These two forms of reasoning are important to science, despite there flaws. Inductive reasoning is mostly used when forming hypotheses and deductive reasoning is used when scientist are applying theories to specific situations. So chances are if you're writing a hypothesis that's inductive. Once you're figuring out how it applies to the real world that's deductive. You may have heard something called a scientific law. A law is a statement recording an action that is true. Example: All life is based on cells. This shows that something called life is based on the actions of cells. This does not say anything about the theory, which remember, explains the phenomenon. All a scientific law is a statement on a phenomenon. This gets confused a lot so I'll say it again. A scientific law is a true observation, a scientific theory is there to explain the observation. I should say that both a law and a theory can be proven wrong. A law does not mean true. A theory is not a law that's proven wrong. This is something that people get wrong all the time. Look at any article that mentions the theory of evolution. I guaranty a hundred percent that someone will say that evolution is wrong because it is not a law. If you every see something like this, please, link to this video and tell them to subscribe to my channel. So now go ahead and do the problems and in the next part we are going to be using our good friend pre-algebra to convert in the metric system.