Substantial revisions to clarify the post's core claim, including but not limited to this summary at the end:
Summary
Effective Altruism claims that there is a large funding gap for cheap well-understood developing-world interventions.
Even the most aggressive plausible construal of this claim implies an annual funding gap that could be covered completely by existing major institutional donors.
If this is true, it implies opportunities for comparatively cheap experiments (relative to the endowments of major donors in the space) with extremely high information value.
Such experiments have not happened either because they are impossible, or because the relevant institutional donors think they have better things to do with their money.
Neither scenario suggests that small donors should try to fill this funding gap. If they trust big donors, they should just give to the big donors. If they don't, why should they believe a story clearly meant to extract money from them?
How many lives do you think can be saved for between $5k and $10k?
The smaller the number, the more "~$5k per life saved" looks like an impact certificate you're buying from Good Ventures at a price assessed by GiveWell, rather than a serious claim that for an extra $5k you can cause a life to be saved through the intervention you funded.
The larger the number, the more the marginal cost looks like the average costs for large numbers of lives saved (and therefore the "why don't they do an experiment at scale?" argument holds).
Claims that you can make the world different in well-specified ways through giving (e.g. more lives saved by the intervention you funded) imply the latter scenario, and substantively conflict with the former one.
Substantial revisions to clarify the post's core claim, including but not limited to this summary at the end:
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