NextBurgh, PA          @VannevarB      About      Pittsburgh Murals
May 19, 2009

Experience and Karl Popper's Three Worlds

Sir Karl Popper is a philosopher of science and a student of the scientific process. He describes science through an ontology of three worlds, as shown below. World-One is the physical realm, World Two is the realm of subjective reality, and World Three is the realm of objective knowledge.



The worlds are positioned so that only the first two and the last two can interact; World One and World Three cannot interface except through the intermediation of World Two.

World Three contains our accumulated scientific knowledge, which is enshrined in (but does not consist of) the devices that store it.

Popper maintained that the activity of understanding consists of operating with World Three objects, and described World Three as an arena where linguistically formatted theories can be critically discussed.

World One : The Physical World

Let's say that there's a balloon in your house. You, the balloon, and the house are in World One, the physical world. You observe the balloon through the morning and afternoon. As the day continues, the balloon gets bigger and bigger. You measure the balloon and keep track of the results. This data, these measurements without interpretation, are in World One.

TimeBalloon Size
08:00 AM12 inches
09:30 AM12.5 inches
11:00 AM13 inches
1:30 PM14.5 inches


World Two : Subjective Reality

You wonder about this. What's going on? Your thinking takes place in World Two, the world of subjective reality. Opinions, assumptions, and perceptions abound. As you think, you decide to analyze the measurements:
TimeBalloon SizeElapsed TimeChange in Size
08:00 AM12 inches00
09:30 AM12.5 inches1.5 hours.5 inch
11:00 AM13 inches3 hours1 inch
1:30 PM14.5 inches4.5 hours1.5 inches

And you develop a graph of the data:


You develop a theory: the size of the balloon increases with time. This is not a bad theory; it explains the observed phenomena. You develop a formula to explain the relationship: Growth(inches)= Time(hours) / 3. You're still working in World Two. You feel very good about this.

World Three : Objective Knowledge


You decide to involve others in your thoughts; you'd like to have your findings recognized and accepted. You branch out from World Two (subjective reality) and tentatively step into World Three (objective knowledge). You contact several friends, explain your data and your theory. You introduce your theory to World Three.

Your buddy Ralph, ever the naysayer, says "I can't disagree with your findings. The value of a good theory is its usefulness to predict. Tell me: what size will the balloon be at 3:00 pm? You look at your chart and your formula, and say quite confidently, "At 3:00 pm, the balloon will have grown another half-inch, for a total growth of 2.0 inches, and a total size of 14 inches."


At 3:00 pm, you measure the balloon and your prediction was right on. You nailed it. You notify your associates, and they congratulate you on your new Law of Science. You publish your results and the New Law of Science for the world to use and benefit from. You've increased our knowledge of the universe. MaryLou, however, remains a skeptic. "I don't think you're right, but I can't prove you're wrong."

You decide to offer MaryLou some food for thought. You say, "Listen-- At 4:30 pm the balloon will be 14.5 inches inches, and at 6:00 pm the balloon will be 15 inches. You'll see."



Past Behavior is no Guarantee of Future Performance

At 4:30 pm, you measure the balloon, expecting it to be 14.5 inches, and find that the size has decreased to 13.5 inches. At 6:00 pm you measure again, hoping that the balloon is back on track, and you see that the size has decreased to 13 inches.



You notify your friends, share the numbers, and tell them that your new Law of Science has been disproved (falsified). Mary Lou consoles you, "It was a good theory; it explained the known phenomena. Something else must be going on. We'll figure it out". Your proposed theory is banished from World Three.

The next day Barry calls the group with a new theory. He's working in World Two. He suggests that it wasn't the passage of time, but instead it was sunlight that made the balloon grow. (It got real cloudy after 3:00 pm.) He builds on the previous process, develops a new theory, and it passes his initial test.

He sends it into World Three by publishing his data and theory. Others run the experiment at their house, and they're able to duplicate his results. Nobody is able to disprove it. Barry's Law is accepted into World Three, at least until such time as somebody can disprove it.

Karl Popper's Philosophy of Science


Karl Popper said this process of Falsification within Three Worlds is the essence of science. World One presents events and phenomena. World Two develops personal concepts. World Three rejects falsified concepts and accepts other concepts until such time as they are falsified. Science includes the test tubes and experiments, but it's fundamentally about publication, review, acceptance, and falsification.

Popper described science as an evolutionary process in World 3, in which scientists offered bold conjectures to explain phenomena and the community refuted or accepted them. He describes knowledge through the interrogatives:
"In seeking pure knowledge our aim is, quite simply, to understand, to answer how-questions and why-questions. These are questions which are answered by giving an explanation. Thus all problems of pure knowledge are problems of explanation."





Experience and Popper's Three Worlds


We thank the Dear Reader who is still with us. What does Experience have to do with Popper's Three Worlds? Let's go back to the Venn diagrams and remember the constraint: World One and World Three cannot touch; they must be integrated through World Two. What would the Venn diagrams look like for the various combinations of Experience and Knowledge?


No Experience, No Knowledge

What would the chart look like for a person with very practical experience, and very little contact with the body of objective knowledge? The thing that jumps out of this chart to me is that there's he's got a lot of himself, and not much else.


Good Experience, No Knowledge

This is a person who knows the physical world, but isn't going to benefit from any of the common body of objective knowledge.



No Experience, Good Knowledge

This is a person who understands objective knowledge, but has no experience in the physical (real) world; academics and theorists come to mind.



Good Experience, Good Knowledge


This is a person who knows the world and knows the body of objective knowledge. The thing that jumps out of this diagram for me is that the person doesn't get in his own way. This seems a valid representation of most competent people I know.


My take-away is: Experience Matters.


click here for a Karl Popper cartoon.

1 comments:

Anonymous said...

appears to be an error in the no experience/good knowledge illustration

Post a Comment

Comments and Feedback? Love that stuff. Please leave your thoughts in the box below--