Cosmologist Martin Rees will speak in Vancouver about Earth's future in the 21st century

Most people wouldn't have the intellectual confidence to publicly dismiss anything said by famed theoretical physicist Stephen Hawking. But not Martin Rees, the former president of the Royal Society and former director of Cambridge University's Institute of Astronomy, who ripped into his fellow scientist's claim that creation can be explained without any need to inject God into the discussion.

In 2010, Rees told the Independent that after 40 years, he knew Hawking "well enough to know that he has read very little philosophy and even less theology, so I don't think we should attach any weight to his views on this topic".

Rees will give a free public lecture, entitled "A Cosmic Perspective for the 21st Century", at Vancouver's Vogue Theatre at 7:30 p.m. on Monday (October 15). The event is sponsored by UBC's Peter Wall Institute for Advanced Studies.

Last year, the Guardian reported that Rees, one of the world's most famous cosmologists, does not believe in God. But he also told the paper: "Campaigning against religion can be socially counter-productive. If teachers take the uncompromising line that God and Darwinism are irreconcilable, many young people raised in a faith-based culture will stick with their religion and be lost to science."

He has also argued that the scientific community needs as many allies as possible, including religious moderates, to counter fundamentalists.

In his lecture tomorrow night, Rees will address the growing gap between what science enables human beings to do and what's prudent or ethical.

He previously told the Independent that he's a "technological optimist", believing that science will bring forward solutions to enable nine billion people to live in the world by 2050 at an acceptable standard of lviing. However, the long-time member of the Labour Party also described himself as a "political pessimist" because he's not certain that the technology will necessarily be put to proper use.

According to the description on the Peter Wall Institute for Advanced Studies website, Rees's lecture will acknowledge that Earth has been around for 45 million centuries. However, he'll explore why this is the first century in which a single species, human beings, are in a position to determine its future.

This issue was also addressed in his 2004 book, Our Final Hour: A Scientist's Warning, in which he forecast that humanity had only a 50 percent chance of making it through this century.

Rees has published more than 500 papers and is acknowledged as a leading authority on the Big Bang, which describes how the universe expanded.