And then there's a school of thought that holds that, even if AI is possible, the Singularity idea is hogwash — it just looks like an insuperable barrier or a permanent step change because we're too far away from it to see the fine-grained detail. Canadian SF writer Karl Schroeder has explored a different hypothesis: that there may be an end to progress. We may reach a point where the scientific enterprise is done — where all the outstanding questions have been answered and the unanswered ones are physically impossible for us to address.