In a certain sense, the different levels of map are like the shells of a Russian doll
I would order your heirarchy exactly backwards. Description is easy, explanation is hard, prediction is even harder. I can observe that (made-up example) 20% more subjects lose weight on a low carb diet than on a low fat one. Explaining that is much harder. Predicting how any of various other diets would work for weight loss is harder still. Your larger circles oddly require more data and will generally be less certain. Thus, I find it a little odd to say that description is a subset of prediction, when you can describe far, far more than you can predict.
Most sciences assign a hierarchy to these concepts based on their difficulty, or “impressiveness.” I think this is often harmful. You need to first describe things before you can start explaining them. To a certain degree, you need to explain things in order to predict them (or at least admit you can’t explain them so you don’t over rely on your predictions).
Description is easy, explanation is hard, prediction is even harder.
I can’t think of why I would have disagreed with this! If I seemed to disagree with it anywhere in the post, that was unintentional. The point is that description is the easiest and prediction is the hardest, thus the last to be reached, thus the outer level of the shell. Which is impressive, but only because it’s harder, because you have to do all of the work involved in description before you can explain, and have a complete explanation before you can predict.
I believe Psychohistorian’s criticism is primarily about the “shell” image: if interpreted as a Venn diagram, it gets the subset inclusion hierarchy backwards. Judging by your comment above, you have a different metaphor in mind—something like a map in which an individual starts in the center and effortfully moves to the edge.
I would order your heirarchy exactly backwards. Description is easy, explanation is hard, prediction is even harder. I can observe that (made-up example) 20% more subjects lose weight on a low carb diet than on a low fat one. Explaining that is much harder. Predicting how any of various other diets would work for weight loss is harder still. Your larger circles oddly require more data and will generally be less certain. Thus, I find it a little odd to say that description is a subset of prediction, when you can describe far, far more than you can predict.
Most sciences assign a hierarchy to these concepts based on their difficulty, or “impressiveness.” I think this is often harmful. You need to first describe things before you can start explaining them. To a certain degree, you need to explain things in order to predict them (or at least admit you can’t explain them so you don’t over rely on your predictions).
I can’t think of why I would have disagreed with this! If I seemed to disagree with it anywhere in the post, that was unintentional. The point is that description is the easiest and prediction is the hardest, thus the last to be reached, thus the outer level of the shell. Which is impressive, but only because it’s harder, because you have to do all of the work involved in description before you can explain, and have a complete explanation before you can predict.
I believe Psychohistorian’s criticism is primarily about the “shell” image: if interpreted as a Venn diagram, it gets the subset inclusion hierarchy backwards. Judging by your comment above, you have a different metaphor in mind—something like a map in which an individual starts in the center and effortfully moves to the edge.
That makes more sense.