In addition to expansion of his scientific interests, Rees has written and spoken extensively about the problems and challenges of the 21st century, and interfaces between science, ethics, and politics. In his books
Our Final Hour and
On the Future, Rees warns that humanity faces significant
existential risks in the 21st century due to technological advancements, particularly in
bioengineering and
artificial intelligence. He estimated a 50% chance of human extinction during the 21st century, but remains optimistic that if the risks are successfully managed, technology could drastically improve standards of living. In 2007, he delivered the
Gifford Lectures on
21st Century Science: Cosmic Perspective and Terrestrial Challenges at the
University of St Andrews. He made two
TED talks on existential risks. Rees thinks the
search for extraterrestrial intelligence is worthwhile and has chaired the advisory board for the "
Breakthrough Listen" project, a programme of
SETI investigations funded by the Russian/US investor
Yuri Milner. In August 2014, Rees was one of 200 public figures who were signatories to a letter to
The Guardian expressing their hope that Scotland would vote to remain part of the United Kingdom in September's
referendum on that issue. To mark the 300th anniversary of the
Board of Longitude in 2014, he instigated a programme of new challenge prizes of £5-10m under the name "
Longitude Prize 2014" for which he chairs the advisory board. The themes of the first two prizes are the reduction of inappropriate antibiotic use, and enhancing the safety and independence of dementia sufferers. The Longitude Prize on Dementia was announced in 2022. In 2015, he was co-author of the report that launched the
Global Apollo Programme, which calls for developed nations to commit to spending 0.02% of their GDP for 10 years, to fund coordinated research to make
carbon-free baseload electricity less costly than
electricity from coal by the year 2025. In his general writings and in the
House of Lords, his focus has been on the uses and abuses of advanced technology and on issues such as
assisted dying, preservation of dark skies, and reforms to broaden the post-16 and undergraduate curricula in the UK. He is also a current member of the House of Lords Science and Technology Committee. == Selected bibliography ==