[...] but you never answered my question: when and how do we decide that a theory is without substantial merit?
This is very much a key question when it comes to politicized science.
For instance, we can dismiss anyone trying to introduce "flat earth theory" or "intelligent design" as justification for a political position, let alone for scientific discussion. It's not that we can't ever question our beliefs about those things; it's just that the evidence is in, the "debate" has already happened, and scientific orthodoxy came down on the other side (the earth is round; present life evolved from simpler forms via natural selection) -- so if someone wants to reintroduce them as legitimate issues worthy of debate, they have some heavy lifting to do.
I would characterize this heavy lifting as requiring the following:
State the orthodox conclusion, and note that you are suggesting an alternative.Clarify whether you agree that the orthodox conclusion was reasonable, given what was known previously.Propose your new conclusion, and suggest how the evidence (old and/or new) supports it better.That's the simplest case for challenging orthodoxy; the situation is a bit more nuanced with an item like The Bell Curve (TBC).
While the scientific debate has been had and many of the book's conclusions have been rejected as bad science, it's also true that it may include some perfectly valid statements which have simply been taken out of context and used in misleadingly political ways.
If you're arguing, for example, that TBC has been unfairly written off for political reasons, then, you need to be clear about which specific parts of it (conclusions or statements) you're referring to and whether you're challenging the orthodoxy on those items or merely pointing out that they've been unreasonably politicized despite being valid.
Note that you can't just go saying "this book is unfairly maligned" -- because as a whole, it was maligned for very good reasons. If there are particular parts of it which you believe to be salvageable, you need to make it clear that you're not trying to defend the book as a whole.
If (on the other hand) you believe that it's valid as a whole, then you're asking for settled orthodoxy to be re-examined on numerous points -- which requires the rather heavier lifting above for each of those points.
W.
#LWaC #BellCurve #racism
(This discussion started with the item I linked and responded to here on CWRE.)