Reading Okasha's "Evolution and the levels of selection" he talks about "the levels of selection problem." There is a bit of a problem with this opening chapter because, while he talks about why the levels of selection problem is a problem, he doesn't define what the levels of selection problem is.
The opening line from the book..
"The levels of selection problem is one of the most fundamental in evolutionary biology, for it arises directly from the underlying logic of Darwinism. The problem can be seen as the upshot of three factors..."
I think what he means by the "levels of selection problem" is that selection acts on many levels, and what is adaptive at one level may be maladaptive at another. Therefore we can not define selection as acting at one single level, and studying it as such is likely to lead to incorrect conclusions - studying selection is not a simple process. Can anyone provide a firm definition of what Okasha, and the general community on the matter, mean by the "levels of selection problem"?
(Note: The factors are the abstract nature of the principles of selection, the hierarchical nature of biological organisation, and the process of adaptation via natural selection).