Is there a Hard Problem? Photo: Flickr/A Health Blog
Show Hide image

A hard problem for soft brains: is there a Hard Problem?

Daniel Dennett wants to convince Tom Stoppard that there is no Hard Problem.

Oh, to have been a fly on the wall when the philosopher Daniel Dennett chatted with Tom Stoppard. The conversation took place after a performance of Stoppard’s new play about consciousness, The Hard Problem. A few days earlier, Dennett had told an audience at the Royal Institution (RI) that there is no “Hard Problem”.

The play’s name comes from the label that the Australian cognitive scientist David Chalmers gives to the task of understanding consciousness. This is hard, he says, because no physical phenomena will ever be found to account for the emergence of conscious experience. It is a statement of faith but one that has garnered plenty of support and clearly caught Stoppard’s attention.

Consciousness is a tough nut to crack. Scientists aren’t sure how to define it and they don’t know how it – whatever “it” is – emerges from the squidgy, biological matter of the brain. Somehow, billions of neurons connect and give us the ability to sense the outside world and have what we describe as “feelings” about our experience.

To Stoppard, consciousness is an almost supernatural phenomenon – something beyond the reach of science. His play suggests that those who indulge in spiritual beliefs might be more successful in hunting down the root of consciousness, as if consciousness inhabited some realm beyond physics, chemistry and biology.

Dennett, on the other hand, thinks that we may have already solved the problem of consciousness with a coterie of small-scale, rather banal explanations. The non-mysterious ways in which the brain creates our sensory experience might be the only ingredients we need to explain how it is that we are aware of feeling something.

He expands on this possibility in his contribution to a new collection of essays at edge.org that asks the question: “What scientific idea is ready for retirement?” He chooses the Hard Problem (even though, he says, it isn’t actually a scientific idea) and suggests we should approach all of its difficulties in the same way as scientists approach extrasensory perception and telekinesis: as “figments of the imagination”.

The central issue concerns our trouble with believing in the physicality of things we cannot see or touch. Software, Dennett suggested at the RI, provides a good example. Everyone agrees that software exists and performs tasks that are far from mysterious. But what is it made of? Lines of code written on a piece of paper do nothing. When written into a computer, they become abstract information encoded in the electronic state of silicon chips – we know that they are there but they are transformed. However hard that is to grasp, it doesn’t
make software spiritual or take it beyond analysis.

A word of caution: there is always a danger of interpreting our scientific struggles within a familiar paradigm. Newton discovered his “clockwork heavens” in an age when accurate means of measuring time were the central goal of many scientifically minded colleagues. Einstein’s special relativity, which defines the fundamentals of the universe in terms that reference light and signals, was birthed in the era of the electric telegraph. Neither was the final word.

These days, much of physics and biology focuses on issues of information transfer, probably because computing now plays such a significant role. So it is possible that Dennett’s software analogy is an innocent sleight of hand. It may be that we haven’t yet encountered the paradigm that will allow us to frame a good understanding of consciousness.

That would certainly make consciousness a hard problem to solve right now – but still not the Hard Problem.

Michael Brooks holds a PhD in quantum physics. He writes a weekly science column for the New Statesman, and his most recent book is At the Edge of Uncertainty: 11 Discoveries Taking Science by Surprise.

This article first appeared in the 09 April 2015 issue of the New Statesman, The Anniversary Issue 2015

Davide Restivo at Wikimedia Commons
Show Hide image

Scientists have finally said it: alcohol causes cancer

Enough of "linked" and "attributable": a new paper concludes that alcohol directly causes seven types of cancer.

I don't blame you if you switch off completely at the words "causes cancer". If you pay attention to certain publications, everything from sunbeds, to fish, to not getting enough sun, can all cause cancer. But this time, it's worth listening.

The journal Addiction has published a paper that makes a simple, yet startling, claim: 

"Evidence can support the judgement that alcohol causes cancer of the oropharynx [part of the throat], larynx, oesophagus, liver, colon, rectum and [female] breast"

So what's especially significant about this? 

First, scientists, unlike journalists, are very wary of the word "causes". It's hard to ever prove that one action directly led to another, rather than that both happened to occur within the same scenario. And yet Jennie Connor, author of the paper and professor in the Preventive and Social Medicine department at the University of Otago, New Zealand, has taken the leap.

Second, alcohol not only causes cancer of one kind – the evidence supports the claim that it causes cancer at seven different sites in our bodies. There was weaker evidence that it may also cause skin, prostate and pancreatic cancer, while the link between mouth cancers and alcohol consumption was the strongest. 

What did we know about alcohol and cancer before?

Many, many studies have "linked" cancer to alcohol, or argued that some cases may be "attributable" to alcohol consumption. 

This paper loooks back over a decade's worth of research into alcohol and cancer, and Connor concludes that all this evidence, taken together, proves that alcohol "increases the incidence of [cancer] in the population".

However, as Connor notes in her paper, "alcohol’s causal role is perceived to be more complex than tobacco's", partly because we still don't know exactly how alcohol causes cancer at these sites. Yet she argues that the evidence alone is enough to prove the cause, even if we don't know exactly how the "biologial mechanisms" work. 

Does this mean that drinking = cancer, then?

No. A causal link doesn't mean one thing always leads to the other. Also, cancer in these seven sites was shown to have what's called a "dose-response" relationship, which means the more you drink, the more you increase your chances of cancer.

On the bright side, scientists have also found that if you stop drinking altogether, you can reduce your chances back down again.

Are moderate drinkers off the hook?

Nope. Rather devastatingly, Connor notes that moderate drinkers bear a "considerable" portion of the cancer risk, and that targeting only heavy drinkers with alcohol risk reduction campaigns would have "limited" impact. 

What does this mean for public health? 

This is the tricky bit. In the paper, Connor points out that, given what we know about lung cancer and tobacco, the general advice is simply not to smoke. Now, a strong link proven over years of research may suggest the same about drinking, an activity society views as a bit risky but generally harmless.

Yet in 2012, it's estimated that alcohol-attributable cancers killed half a million people, which made up 5.8 per cent of cancer deaths worldwide. As we better understand the links between the two, it's possible that this proportion may turn out to be a lot higher. 

As she was doing the research, Connor commented:

"We've grown up with thinking cancer is very mysterious, we don't know what causes it and it's frightening, so to think that something as ordinary as drinking is associated with cancer I think is quite difficult."

What do we do now?

Drink less. The one semi-silver lining in the study is that the quantity of alcohol you consume has a real bearing on your risk of developing these cancers. 

On a wider scale, it looks like we need to recalibrate society's perspective on drinking. Drug campaigners have long pointed out that alcohol, while legal, is one of the most toxic and harmful drugs available  an argument that this study will bolster.

In January, England's chief medical officer Sally Davies introduced some of the strictest guidelines on alcohol consumption in the world, and later shocked a parliamentary hearing by saying that drinking could cause breast cancer.

"I would like people to take their choice knowing the issues," she told the hearing, "And do as I do when I reach for my glass of wine and think... do I want to raise my risk of breast cancer?"

Now, it's beginning to look like she was ahead of the curve. 

Barbara Speed is a technology and digital culture writer at the New Statesman and a staff writer at CityMetric.