Wealth Tax: The Scientific Evidence
Executive Summary
A comprehensive Twitter/X thread by Kasper Bjørkskov summarizes the academic literature on wealth taxes, concluding: the science is settled. People opposing wealth taxes are either protecting their own wealth or letting ideology override evidence. The thread marshals IMF, OECD, IZA, EU Tax Observatory, and NBER research.
Why relevant for Floyd: This is ammunition for the CommonWealth/UBI Works policy arguments. The fear of “capital flight” and “wealth destruction” from progressive taxes is empirically refuted.
The Evidence
Inequality Kills Growth (Not Wealth Taxes)
- IMF study: “Higher inequality lowers growth” — cross-country data, decades of evidence
- OECD: Rising inequality reduced cumulative GDP growth in European economies by up to 6%
- The thing opponents claim will hurt the economy is already hurting it
Wealth Taxes Don’t Kill Jobs
- IZA study (Norway): Wealth tax across thousands of firms, 12 years → “no evidence wealth tax adversely affects employment”
- Positive relationship found: owners invest in businesses/people instead of parking wealth in passive assets
Rich People Don’t Flee
- EU Tax Observatory: 1pp tax increase → reduced wealthy taxpayer numbers by only 0.003% to 0.03% per year
- NBER: Negligible migration effects from wealth taxation
- Norway real-world test: Only ~150 millionaires left after 0.3pp increase
Nordic Countries Disprove the Narrative
- Sweden: more billionaires per capita than the US, had wealth tax for decades
- Denmark and Norway: match or exceed US in hourly labor productivity
- High taxes + high productivity + high wellbeing = the Nordic model works
Key Takeaway for Policy Arguments
- The “capital flight” argument is empirically weak (0.003-0.03% per year migration)
- The “kills jobs” argument is empirically false (positive correlation in Norwegian data)
- The “hurts growth” concern is backwards — it’s inequality that kills growth, not taxes on it
- The real opposition is ideological and self-interested, not evidence-based
Timeline
- 2025-12 | Thread by Kasper Bjørkskov published summarizing wealth tax research [Source: Readwise Reader, “The science on wealth taxes is settled”, X/@KasperBjorkskov, 2025-12]
- 2026-04-13 | Brain page created from Readwise ingestion [Source: Readwise Reader ingestion, 2026-04-13]
See Also
- CommonWealth — Floyd’s advocacy org
- UBI Works — Canadian UBI advocacy
- canada-housing-land-value-tax — the land version of these taxes
- progress-and-poverty-henry-george — theoretical foundation