Hi again, this is the last in a four part series answering the question what is science taken from the items of the natural science quiz by Larry Flamer. So we'll be looking at these four items here firstly. So you can see there in red there are some concepts there what I want you to do with those is to pause the film and I want you to list them in what you think is the most scientific all the way down to the least scientific.
draw a line and then underneath that line place any concepts there which you think are not scientific. So have a go at that, pause and then come back to the video. Welcome back!
So this is my attempt at organising that list into scientific and non-scientific ideas. So you can see there the two that I've placed below are Ancient Texts and Divine Revelation. So when we look at...
why those are deemed to be non-scientific concepts because visitations from ghosts and information from angels or aliens generally tend to happen just to one person and so therefore they're untestable because no one else gets visited by the same angel and get the same message and they're unverifiable. The same thing with ancient texts and whether they are scribed onto stone or onto animal hide or... or come from an authority like Aristotle, just because they're ancient does not make them correct, which a lot of people who promote pseudosciences actually claim, that knowledge, ancient knowledge, is better than modern knowledge.
Probably a better way of having a look at these concepts is via a Venn diagram. So you can see there, divine revelation and knowledge just because it's ancient and knowledge just because it's modern are not necessarily scientific. What makes them scientific is they need to go through this process over there on the left. In the middle there, you can see hunches and insights and anecdotes or case studies. And these are an important part of science, but they can also be non-scientific because they inform the creation of hypotheses.
So what we'll be doing now is we'll be going through those. So as an example of hunches and insights is this guy here, Kekulé. So one day, Kikele was a famous chemist, and during a daydream, he hypothesized, or he came up with, the idea of the oborus to explain the structure of benzene, which you can see there is a six-carbon molecule. And so from this, he was able to hypothesize that...
benzene was six carbons and formed a ring. From that he developed hypotheses, experimented, and was able to verify that that was indeed the structure. And subsequently we now have modern methods which we can verify that that is the correct structure for benzene. So when we have a look at these definitions of hypothesis, now quite often we tell students that a hypothesis is a guess or an educated guess when in actual fact it's a lot more than that. A hypothesis is a testable statement that explicitly predicts a causal link between two or more variables.
So let's have a look at a couple of examples. Hypotheses have the general form of an if-then-because statement. So let's look at an experiment where a child gets plants and is investigating whether light is required for plants to grow. So they might write a hypothesis like this.
If plant A is put in the sun and plant B is put in the dark, So that would be their independent variable, the amount of light. Then plant A will grow more than plant B. So this is the prediction.
What you also note is that they're actually predicting the direction of effect there, that plant A will grow more than plant B. That's their dependent variable. And then the last part of our hypothesis is the explanation.
So this student has researched a bit, found out about photosynthesis, and says... because this is how plants make their food for growth. Now this is what we would call a laboratory experiment because a lot of the variables can be controlled and manipulated and so forth. Let's have a look at another example where the control of the variables is impossible.
So this researcher is looking at the differences between boys and girls. So they're looking at how into cars boys and girls are. So they formulate this hypothesis.
So if boys are more into cars than girls, so the sex of the person there is the independent variable, so that's the variable which is going to be different between the two groups, then more boys will go to Grand Prix races. So they're going to measure their dependent variable, grand prix attendance, and they finally give a reason. So unlike the first example, where they were able to control the variables, they can't truly control the variables here, and the variables are a lot looser.
So this is what we will call a natural experiment. But what's important here is that there's the manipulation of the independent variable and the measurement of a dependent variable. So from hypotheses, these are then tested by experiments, which then give us conclusions.
And then from that, ultimately, you might get something which is a law. And a law, a lot of people think it sits above a theory in terms of they're important to science. But really, all a law is is a statement of relationship between variables, but it's not explanatory.
So for example, Newton's three laws of motion, they describe how things move, but they don't... actually explain why they do so. The same with the GAS laws or Mendel's laws of inheritance.
Hooke's law just looks at the behavior of springs and the law of conservation of mass. They don't then go on to explain what why there is a relationship between those variables. They simply state there is a relationship.
The queen of all knowledge within science is a theory and a theory is an explanatory framework and it needs to be supported by multiple lines of evidence that has explanatory power, which is what a law does, but it also needs to have predictive power. So a theory should be able to generate hypotheses, which can then go and explore different aspects of that theory. So, for example, cell theory, germ theory within biology, then there's quantum field theory or quantum mechanics.
theory of special relativity and general relativity within physics and string theory, big bang theory, these are all theories because they explain much much more aspects of the phenomenon than an actual law does. So where a theory in every day would be a qualitative guess, that is actually what we're trying to aim for. within the sciences in developing theories.
Theories are our top explanations that we have in science. So let's have a look at this statement here. Anything done scientifically can be relied upon to be accurate and reliable.
So you can see a screenshot there of a Google search for broccoli is good for you. So these two items here, they state that broccoli is good for you, whereas these two links here question how effective broccoli is. or how good for you broccoli is. So which is it?
And quite often this occurs with cutting-edge science. And especially when you're not an expert within a particular field, the best plan of attack there is to go with the weight of evidence. You need to look at everything, all the research which has come before this, and see where the current finding for this particular piece of research fits within all of that. And so... what we should do when we're not experts in the field is look at the weight of evidence.
Let's have a look at the disagreements between scientists, one of the weaknesses of science, and let's look at the research into what is light and what is the nature of light. So for example, Newton, when he was doing his research, he was saying that wave was a particle, and so he did a whole heap of experiments and he was able to show that light was a particle. However, this guy Huygens, he also did experiments, but his experiments showed that light was a wave. So they argued backwards and forwards, and it wasn't until modern science and a whole heap of other scientists came along and settled the argument, and essentially what they said was that light has a dual nature, that it both has wave-like properties and particle-like properties, depending upon the situation.
And... So what we can see there is that within science there is disagreement and disagreement is actually encouraged. But the disagreement between the two camps may actually end up with being a third possibility where they are actually both correct, where both parties are correct.
And you can see here in the nature of light. So here, let's have a look at science can be influenced by race, gender, nationality or religion of the scientist. So yes, at a basic level, because we're all humans, our interpretation of data and how we conduct the experiments and so on are certainly influenced by our biases which come from our race, our gender, nationality, religion and so on.
But because of the nature of science, in that science is firstly peer-reviewed, science in the long run is actually self-correcting. On a societal level, society actually determines the areas of science we actually investigate. So for example, within the US, when George W. Bush was in power, the second, he actually disagreed with research into stem cells. And so for a long time, the US fell further and further behind in terms of stem cell research.
So you can see there the science which is investigated by scientists is actually influenced by politicians and society at large. So that most certainly is true. And the last statement that we'll have a look at is scientists have solved the major mysteries of nature. When we have a look at the number of species that biologists have actually discovered, estimates place the percentage of species discovered as 14% so there are still plant many plants and animals in rainforests at the bottom of the oceans And so on which remain undiscovered.
So that's within biology alone When we have a look at physics When we have a look at the amount of stuff in the universe, we only actually comprise 0.4% of stuff in the universe There is this stuff called interlactic gas, which is mainly hydrogen. That's 3.6% But then the remainder, 96%, is stuff called a dark energy and dark matter. And the reason why it's called dark is because we aren't able to observe it with our instruments. So we call it dark energy and dark matter.
So there is plenty of scope there for research within biology and also in physics. So here are the references that we have. And to finish off with...
Here is a few words from Carl Sagan.