Bill Gates has thrown his weight behind a “robot tax” and ‘Human Reserved’ jobs, aiming to mitigate the negative impacts of artificial intelligence on employment.

Writing in his Gates Notes blog, Gates argues that the current tax system encourages employers to replace human workers with machines. Implementing a robot tax would slow this trend, while also raising funds for retraining programs and bolstering safety nets.

Gates also suggests designating certain jobs as ‘Human Reserved,’ meaning AI cannot perform them due to economic or moral reasons. For instance, he cites the emotional impact of an AI delivering bad health news to a patient as a compelling rationale for such exclusions.

Both proposals could significantly curtail profits for major AI companies but Gates acknowledges that many questions remain about who will set these rules and exactly what they might entail.