Leveraging blockchain to benefit and protect human society

The increasing integration of autonomous and algorithmic systems into social infrastructures requires robust frameworks that ensure the protection of human values and societal rules. This dissertation investigates the potential of blockchain technology to address governance and protection challenges in four different areas: Education, Artificial Intelligence (AI) alignment, social decision-making, and decentralized financial markets. In these areas, this dissertation investigates how blockchain-based mechanisms can be designed to improve transparency, resilience, and fairness in systems where traditional safeguards are not sufficient. The research follows a simulation-driven methodology and applies agent-based and system dynamic models to evaluate the performance and societal impacts of novel blockchain-based solutions. The first study develops and tests a token economic system within a South African education platform and shows that optimized token reward systems can significantly improve student engagement and reduce inequalities. The second study proposes a novel framework that incorporates Proof-of-Personhood (PoP) to enable enforceable and transparent AI alignment within the concept of AI shielding and ensure that AI systems adhere to human-approved ethical rules. The third study designs a decentralized, anonymous voting mechanism for AI governance and demonstrates its robustness against malicious manipulation through simulations. The fourth study simulates blockchain-based circuit breakers (CBs) in decentralized markets and shows that these mechanisms effectively reduce financial losses for human traders during volatility triggered by fake news, outperforming traditional CBs. Overall, the results contribute to the theoretical and practical understanding of blockchain as a fundamental technology for improving societal protection and well-being.