I came across the blog “Squashed” via Marco in January. What I read has sat in the back of my mind and bugged me, so I have finally taken the time to write about it.
In “Dumb Metaphor Friday: 'Growing the pie',” the author says:
The conservative criticism of redistribution is a claim that conservatives would rather expand the (economic) pie than ensure that it is divided evenly among everybody. The theory is that everybody then even the guy destined to have a smaller piece comes out ahead, even if the pieces aren’t the same size. This argument is apparently very persuasive to people who think pies expand (perhaps when they’re growing on pie trees)? Those of us who have actually baked pies know that they stay the same size—and all you can do is cut them equally.
It's true: the delicious, fruit-filled pastries do not expand. Pie charts do not usually expand, either. If they do, it is only for visual purposes and the chart still represents 100% of whatever is being measured. Many times the thing that is being measured can expand, though.
In this case, wealth does indeed expand. As I have said before, wealth is not a zero-sum and the possibility to create wealth is practically limitless. This means that the effective amount of wealth represented by a slice of the pie (chart) can be greater than the same size slice at a point in the past. This distinction between effective and relative amounts probably means that pie charts are not the best way to measure economic well-being, but I do not think that makes the metaphor dumb or incorrect.
An expansion in actual wealth is an expansion in actual wealth, regardless of whether the relative amount changes on a pie chart or not.
I think a much simpler criticism of forced redistribution would be: it's wrong to steal.
Related: John Altenmueller also has a good reply: “Pies and apples.”