If the scientific method in which we put so much trust cannot be logically justified, should we abandon it entirely? Are we once again lost in the mystery of the universe, resigned to looking to the heavens for signs and portents just as our ancestors did?
I would argue that, yes we are lost in the mystery of the universe but that science is a pretty good map, one which is constantly being revised.
The map is not the territory
No one would ever argue that some lines and shading drawn on a bit of paper are in any way the same as the territory which they represent, but maps give us a practical way of navigating, they give us a way to get where we want to go and tell us what to expect along the way. I think science is similar.
The map is not the territory
No one would ever argue that some lines and shading drawn on a bit of paper are in any way the same as the territory which they represent, but maps give us a practical way of navigating, they give us a way to get where we want to go and tell us what to expect along the way. I think science is similar.
According to Magee, Hume's problem has led almost all scientists to accept that scientific laws cannot be proved
and therefore are not certain. Each time we observe supporting evidence for our theories however, we become more convinced as to their validity. Every time we see the sun rise in the morning, our faith grows that it will also rise tomorrow.
What science does is gives us the most probable explanation given our current level of understanding and there can be no doubt that the results it delivers are of great practical usefulness. The fact that science is useful though doesn't get rid of the nagging problem that it doesn't have a strictly logical basis.
Popper and black swans
This is where Popper was able to make a great contribution. He noticed that there is an asymmetry between proving and disproving something. The classic example is that of the black swan. No number of observations of white swans, no matter how great, can prove that all swans are white, even though that may be our best guess given the available evidence. In contrast, it only takes one observation of a black swan to disprove that swans are white.
This is a great insight, it means that while we can never prove scientific theories, they are extremely sensitive to being disproved. Rather than shrinking from the far reaching implications of this observation, Popper embraces it and concludes that the scientific method should include systematically attempting to falsify our theories.
What science does is gives us the most probable explanation given our current level of understanding and there can be no doubt that the results it delivers are of great practical usefulness. The fact that science is useful though doesn't get rid of the nagging problem that it doesn't have a strictly logical basis.
Popper and black swans
This is where Popper was able to make a great contribution. He noticed that there is an asymmetry between proving and disproving something. The classic example is that of the black swan. No number of observations of white swans, no matter how great, can prove that all swans are white, even though that may be our best guess given the available evidence. In contrast, it only takes one observation of a black swan to disprove that swans are white.
This is a great insight, it means that while we can never prove scientific theories, they are extremely sensitive to being disproved. Rather than shrinking from the far reaching implications of this observation, Popper embraces it and concludes that the scientific method should include systematically attempting to falsify our theories.
Popper in practice
Magee gives the example of the boiling temperature of water. We know that water boils at 100 degrees centigrade. We could carefully repeat our experiments many times and naively conclude that we'd proved this to be true. Taking Popper's approach though we systematically look for situations where our theory doesn't hold. We would soon find that the boiling temperature differs in closed containers and at altitude.
Now we can develop a new theory which is even richer since it must explain why water boils at different temperatures depending on the conditions. The vulnerability of our theory to being falsified becomes a strength in expanding our knowledge.
Magee gives the example of the boiling temperature of water. We know that water boils at 100 degrees centigrade. We could carefully repeat our experiments many times and naively conclude that we'd proved this to be true. Taking Popper's approach though we systematically look for situations where our theory doesn't hold. We would soon find that the boiling temperature differs in closed containers and at altitude.
Now we can develop a new theory which is even richer since it must explain why water boils at different temperatures depending on the conditions. The vulnerability of our theory to being falsified becomes a strength in expanding our knowledge.
What we thought we knew
Almost everything mankind thought they knew in the past has turned out to be false but amazingly we seem to have a psychological bias for believing that current knowledge is in fact the ultimate truth. In contrast, Popper noticed that knowledge of nature is always provisional and may at any time turn out to be false.
Science is not a body of established fact, it’s constantly changing. All we should ask of science is justification as to why one theory should be preferred over another. In practical applications, while we consider established scientific theory as 'fact', we must at the same time realise that it's foundations are insecure and be open to theories being disproved. This ultimately opens the way for more refined and richer descriptions of nature.
Almost everything mankind thought they knew in the past has turned out to be false but amazingly we seem to have a psychological bias for believing that current knowledge is in fact the ultimate truth. In contrast, Popper noticed that knowledge of nature is always provisional and may at any time turn out to be false.
Science is not a body of established fact, it’s constantly changing. All we should ask of science is justification as to why one theory should be preferred over another. In practical applications, while we consider established scientific theory as 'fact', we must at the same time realise that it's foundations are insecure and be open to theories being disproved. This ultimately opens the way for more refined and richer descriptions of nature.
Scientific fact?
Our present scientific method gives us a means of justifying the choice of one theory over another and at the same time provides results of great practical use. However, it's almost certain that the scientific 'facts' we currently take for granted will one day turn out to be at best only part of the story and at worst completely wrong.
I would even argue that given the ubiquitous historical overconfidence that humans have had in their own level of knowledge, the scientific method itself may one day be superseded by an approach which we cannot yet even conceive of.
The series 'Right and Popper' is based on the summary of Popper's philosophy written by Bryan Magee. The introductory post in the series can be read here.
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