It's not just about life, of course; it's about healthy life. Getting frail and miserable and dependent is no fun, whether or not dying may be fun.

Ever since we invented fire and the wheel, we've been demonstrating both our ability and our inherent desire to fix things that we don't like about ourselves and our environment.

In the eye, there is a type of junk that accumulates in the back of the retina that eventually causes us to go blind. It's called age-related macular degeneration.

The aim is to postpone frailty, postpone degenerative disease, debilitation and so on and thereby shorten the period at the end of life, which is passed in a decrepit or disabled state, while extending life as a whole.

Theres no such thing as ageing gracefully. I dont meet people who want to get Alzheimers disease, or who want to get cancer or arthritis or any of the other things that afflict the elderly. Ageing is bad for you, and we better just actually accept that.

It's not just about life, of course; it's about healthy life. Getting frail and miserable and dependent is no fun, whether or not dying may be fun.

Some things tend not to work so well for science - things that rely on substantial written contributions by key experts are a case in point - but even there I tend to keep an open mind, because it may just be a case of finding the right formula.