Our world is a frantic, intellectually combustible place. Opinions are 10 a penny in the age of Twitter. Mature reflection does not play a major part in public discourse. Knee-jerk reaction?

That'll do. Of course, we have great thinkers today, but they are often drowned out by the general cacophony of soundbites and tweets in a world where we value pithiness over argument, where the ability to be smart, or funny, or controversial in a sentence is prized and envied. It does make you wonder what sort of intellectual legacy this generation will leave.

What triggered these thoughts was a news story I read recently about the campaign to save for the nation the childhood garden of Charles Darwin in Shropshire. This was where the scientist had his formative experiences of nature, and where he began to form his ideas about man's relationship to the natural world. He would walk. And he would think. He called the trail through the garden his "thinking path"; he would go gathering thoughts in the way that other, lesser mortals would gather mushrooms. And, of course, these were not ordinary thoughts.

Darwin's mind wouldn't content itself with the 19th-century equivalent of "Bad hair day. Who cares? LOL." He was more concerned with revolutionising the way we felt about human evolution. It conjured an interesting image for me: this great man having the time, the patience and the inclination to take his brain for a walk. There is a proven link between patterns of movement and the way we think, and Darwin's "Thinking Path" is seen as proof that gentle perambulation inspires the brain to be more dynamic.

I'm not saying it doesn't happen these days, but how often would we step out for a walk without being accompanied by our mobile phone? I have noticed this in myself, the need to feel connected (to what, I can't really say) even when you purposefully set out to free your mind. Most of what goes on around us – in the Twittersphere particularly – is, let's face it, rubbish, so why do we find it so hard to liberate ourselves from this din?

Yes, we have the Large Hadron Collider, and our lives are made so much easier by a wealth of technological developments. But the pace of life seems to take its cue from the particle accelerator, and the chance to stop, look and think is an all-too-rare one. Events occur, the public reacts, everyone moves on.

A well-known figure, who has had more than his share of opprobrium delivered by our popular newspapers, said to me recently that the cycle moves so fast these days that, hardly is he in the eye of a storm, with thousands of voices all raised in indignation, than the caravan moves on and everyone's gaze is diverted elsewhere.

He said he was rather pleased by this lack of public attention span, but I'm not so sure. It's as if Darwin, about to discover the secrets of the Universe, suddenly saw a butterfly and forgot what he was thinking.

We can only be grateful that, in those days, they were made of sterner, more intellectually rigorous stuff. And, of course, Twitter hadn't been invented. On the Origin of Species in 140 characters? I think not.

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