Many investigators feel uneasy stating in public that the origin of life is a mystery, even though behind closed doors they admit they are baffled.
No planet is more earth-like than Earth itself, so if life really does pop up readily in earth-like conditions, then surely it should have arisen many times right here on our home planet? And how do we know it didn't? The truth is, nobody has looked.
A permanent base on Mars would have a number of advantages beyond being a bonanza for planetary science and geology. If, as some evidence suggests, exotic micro-organisms have arisen independently of terrestrial life, studying them could revolutionise biology, medicine and biotechnology.
Cancer is such a ruthless adversary because it behaves as if it has its own fiendishly cunning agenda.
Things changed with the discovery of neutron stars and black holes - objects with gravitational fields so intense that dramatic space and time-warping effects occur.
Cancer cells come pre-programmed to execute a well-defined cascade of changes, seemingly designed to facilitate both their enhanced survival and their dissemination through the bloodstream. There is even an air of conspiracy in the way that tumours use chemical signals to create cancer-friendly niches in remote organs.
It will be in the convergence of evolutionary biology, developmental biology and cancer biology that the answer to cancer will lie. Nor will this confluence be a one-way street.
Scientists have no agreed theory of the origin of life - plenty of scenarios, conjectures and just-so stories, but nothing with solid experimental support.
The way life manages information involves a logical structure that differs fundamentally from mere complex chemistry. Therefore chemistry alone will not explain life's origin, any more than a study of silicon, copper and plastic will explain how a computer can execute a program.
For me, science is already fantastical enough. Unlocking the secrets of nature with fundamental physics or cosmology or astrobiology leads you into a wonderland compared with which beliefs in things like alien abductions pale into insignificance.
General relativity is the cornerstone of cosmology and astrophysics. It has also provided the conceptual basis for string theory and other attempts to unify all the forces of nature in terms of geometrical structures.
Should we find a second form of life right here on our doorstep, we could be confident that life is a truly cosmic phenomenon. If so, there may well be sentient beings somewhere in the galaxy wondering, as do we, if they are not alone in the universe.
The birth of science as we know it arguably began with Isaac Newton's formulation of the laws of gravitation and motion. It is no exaggeration to say that physics was reborn in the early 20th-century with the twin revolutions of quantum mechanics and the theory of relativity.
In the frantic search for an elusive 'cure,' few researchers stand back and ask a very basic question: why does cancer exist? What is its place in the grand story of life?
Science, we are repeatedly told, is the most reliable form of knowledge about the world because it is based on testable hypotheses. Religion, by contrast, is based on faith. The term 'doubting Thomas' well illustrates the difference.
Is there anything science should not try to explain? Science is knowledge and knowledge is power - power to do good or evil. Sometimes ignorance is bliss.
Traditionally, scientists have treated the laws of physics as simply 'given,' elegant mathematical relationships that were somehow imprinted on the universe at its birth, and fixed thereafter. Inquiry into the origin and nature of the laws was not regarded as a proper part of science.
If we do discover more than one type of life on Earth, we can be fairly certain that the universe is teeming with it, for it would be inconceivable that life started twice here but never on all the other earth-like planets.
The language of chemistry simply does not mesh with that of biology. Chemistry is about substances and how they react, whereas biology appeals to concepts such as information and organisation. Informational narratives permeate biology.
When I was a student, the laws of physics were regarded as completely off limits. The job of the scientist, we were told, is to discover the laws and apply them, not inquire into their provenance.
