The news hit the headlines this morning that genetic engineers in Hertfordshire want to trial plants that have been genetically-modified with genes from fish: http://www.farmersguardian.com/home/arable/rothamsted-trialling-gm-omega-3-plants/61696.article .
There are several aspects of the arguments around this that are of philosophical interest. They relate principally to the philosophy of rhetoric, the philosophy of science and technology (epistemology, methodological issues), and the philosophy and ethics of precaution/risk. I will explore these briefly in what follows.
My closest philosophical colleague Phil Hutchinson (@phil_hutchinson) has just had a mini ‘twitter-storm’ with Mark Lynas, over this latest GM business. Phil has been making the argument that the evidence does not support the need for fish genes to be put into plants in order to produce fish oil, because the evidence does not support the claim that doing so is beneficial and necessary.
This ‘mirrors’ the argument that my other current close philosophical colleague Nassim Taleb (@nntaleb) and I (@rupertread) have recently had on twitter with Lynas (Go back to Jan.5 if you want to see this ‘twitter-storm’ from the start). Taleb and I made the argument that (e.g.) taking genes from fish and putting them into plants is reckless, because it is unprecautious: it violates the Precautionary Principle. In other words, our argument was not evidentiary but precautionary.
It seems to me that the ‘evidence’ line against GM combined with the ‘precautionary’ line against it catches GM-apologists such as Lynas in a bind. In a pincer movement.
In outline, the full (the two-pronged) case then runs roughly like this (for references to back this up, if desired, see the material on Twitter):
A GM company wants to take genes from fish and put them into a plant: specifically, in today’s furore: they want to produce Omega three GM camelina.
In brief: There is first NO conclusive evidence for heart-related benefits of Omega 3 fish oil, which demonstrate it as beneficial separate from the fish, as a supplement. There is NO evidence that we need fish oil omega 3 over and above that our bodies already convert from vegetable-based ALA Omega 3 from things like flax.
To elaborate somewhat: We’ve had over ten years of hype from food manufacturers and supplement manufacturers about the heart-benefits of fish-sourced Omega 3 oil. But the evidence for benefits is still inconclusive, at best.
Basically there are three types of Omega 3 fatty acids that humans need: ALA (found in plant oils), EPA, and DHA (found in fish oils).
ALA is in flax seeds and hemp seeds as well as other veg (brussels sprouts for example). Our bodies convert ALA in to EPA and DHA.
Over the past decade or so all sorts of wild claims have been made for the benefits of consuming a diet high in EPA and DHA fatty acids. Goldacre has some sport exposing some of the nonsense hereabouts in Bad Science.
However, there are one or two RCTs that do seem to show some benefit of a diet high in EPA and DHA Omega 3 for heart disease, but, and this is important, only when eaten as part of a fresh fish which contains it. There is simply no evidence for EPA and DHA taken as a supplement being beneficial to health. So, the real kicker is, that they cannot say for sure that it is the EPA and GLA and not just the fact that those who eat fresh fish are likely to eat healthier diets in any case and be better off, socio-economically.
So, why would anyone assume that GM camelina with EPA and DHA would work better than the _ineffective_ supplements? No reason whatsoever. Indeed, as noted, while diets high in fish oil do seem to (in a few cases) have benefits, even there it is unclear this is because of some magical properties of the oil, but rather because of other factors that might be related to a diet rich in oily fish.
So, no clear evidence at all that consumption of EPA and DHA as a supplement has health benefits.
When Phil made these points to Lynas and the GM company, they shifted ground away from talking about the alleged health benefits of omega 3 fish oil (to humans) to talking about the health benefits of feeding omega 3 fish oil to fish.
So: there really – clearly — is no clear evidence that we need EPA and DHA in any case, as our bodies convert ALA (from vegetable sources into those). Lynas et al, when pressed, concede this. They then say: this is about improving aquaculture by making fish food. But then we have the same problem: we have no reason to think that even if the GM splicing worked and they could get it into the seeds that this would work for the fish. Oily fish that are high in Omega 3 get it from the krill and shrimps they eat.
This is about salmon-farming! Not, as they tried to mislead us all this morning into thinking, about human health.
Human health would be better served by better balanced diets.
To sum up the case so far: there is no reason to see what the GM wizards are trying to put into the plant from the fish as useful for fish food if there is no evidence for the benefits of Omega 3 fish oil supplements. At this point, when forced into seeing this, the company replied that that’s allegedly why they need to do the research they are seeking to do… Which is close to a concession that there are (few or) no evidentiary grounds for thinking GM fish-omega 3 camelina will be beneficial: But of course, surprise surprise, that is not what their rep said on the Today programme this morning, nor what Lynas were arguing when Phil first responded to him.
The final phase of the argument (at the time of writing) is I think very telling. It runs thus:
Phil Hutchinson @phil_hutchinson
@Rothamsted @mark_lynas consumed as fish. Barely any conc. evidence for supplement benefits. Your version will be akin to consuming a supp.
Kate de Selincourt @Kate_de
But, @Rothamsted & @mark_lynas, since all livestock farming turns more nutrient into less, why not just eat the fish food? @phil_hutchinson
Mark Lynas @mark_lynas
@Kate_de @Rothamsted @phil_hutchinson That’s an argument for veganism. Fine by me, but hardly a realistic way to tackle overfishing.
‘Fine by me’. Lynas has essentially conceded the case. He prefers a problematic techno-fix which lacks evidential support to a behaviourial and political change that is perfectly possible (i.e. for humans to consume less (factory-farmed) fish (from which a profit can be extracted), and find their omega 3 in other ways).
That’s the evidence-based argument against GM (which has to be made in each individual case on grounds specific to that case (in other cases, the argument will be based on poor yield, or on the inputs to the GM-farming being unsustainable, or on alleged damage to human health, or on actual epidemics of superweeds, or on the desperately-problematic political economy of GM; etc etc), and can be made in each individual case I think, with the possible exception of some GM-cotton). The case benefits from a savvy understanding of the nature of evidence-based arguments, obviously, and thus from a sound philosophy of science and technology perspective. But it is essential an ‘empirical’ argument.
The precautionary argument is different. It is philosophical from the get-go. It is an argument about where the burden of proof lies.
This is in my view the deepest argument against GM: a precautionary one which shifts the burden of proof. It’s no longer about one trying to find a particular counter-argument to claims that GM-enthusiasts are making: it’s suggesting that the onus is rather on THEM to establish the safety of the technology that they are puffing.
The precautionary case against GMOs, in brief, runs thus: If we (for example) take a gene from a fish and put it in a plant, a move utterly without precedent in the whole of evolution, we are recklessly fiddling with and unavoidably changing a system we don’t fully understand and doing something novel whose consequences we cannot possibly predict. This is a reckless gamble, stupid in the short- to medium- term, unconscionably short-sighted and selfish in the long term, as we risk imposing a world of new danger on those who are yet even to be born. We are launching a vast uncontrolled natural (sic.) experiment. The consequences for superweeds, for damaging biodiversity, for creating dangerous mutations, and possibly directly for human health, are unforeseeable. There is a strong precautionary argument against GM, or at the very least in favour of keeping some parts of the world (e.g. an island-nation!) GM-free. IF GM could be properly safely researched to determine what bad ‘side effects’ it may have, then I would favour such research, in good empirical fashion. But it mostly can’t – because it can only be properly ‘researched’ in this way outside the laboratory. In this regard, it differs profoundly from most medical advances, for instance.
This is the terrible dilemma of field trials for GM: The more extensive they are, the more they resemble conditions in the real world, the longer-term they are, then the more reliable they are – BUT also, the more dangerous they are. The more likely it is that they will escape their confines, affect the broader ecosystem, produce unexpected and dangerous drift of genetic materials, etc. . One can’t get the evidence one needs to assess GM with without creating vast uncontrolled new risks.
If we in Britain as a nation contaminate our countryside with GMOs, then that can never be undone. Simple caution and commonsense enjoins – overwhelmingly – against such recklessness.
Defenders of GM sometimes say that there is an absence of evidence of harm from GM. Even if this is true, it is not good enough. What the precautionary argument shows is that we need evidence of absence of harm from GM. And that is what we don’t have. And what will be very hard ever to get without taking an unconscionable risk.
That is the point of the precautionary principle.
Until we have ultra-long-term large-scale trials which cannot contaminate the surrounding countryside, then GM must be considered unsafe. Such trials are at present impossible to carry out. They might one day be possible, though I doubt that they ever will be (this is the dilemma expressed above). If they ever were, then, rather than jumping in precipitously to make a quick buck (as is happening at Rothampsted today) we would then need to wait dozens of years for the results.
In other words, I have argued that one current impossibility is to adequately research contamination, possible damage to biodiversity, etc., without actually potentially causing limitless such damage. One somehow needs long-term (generations of ) trials, in the natural environment, but contained. Something like a huge part-permeable dome that somehow lets in what you want to let in (e.g. sun, rain) in an unaltered way without letting out the GM-crops, over an area of many square miles. Good luck with that…
I am sometimes accused of inconsistency, in making this kind of argument. For, as I’ve made clear in previous posts on this site, I am, like any reasonable person, a fan of climate science, which is vital to the survivability of our species, as we breach the limits to growth. So, why not of ‘GM science’? But this alleged parallel with manmade climate change is very weak. That is a matter of science; while GM is a technology.
Of course genetics is science, but genetic engineering, as the name suggests, is not: it is engineering, i.e. technology. GM is a technology, and so we should be very wary of GM-advocates dressing themselves up in the clothing of science. It is not ‘anti-science’ to oppose GM technology. There are strong empirical and precautionary arguments for doing so.
The parallel in relation to climate is with geo-engineering, not with climate science! And I’m no more a fan of genetic engineering than of geo-engineering, which involves perhaps the ultimate hubristic lack of precaution (or of ethics)… That is: It seems to me, as I’ve sketched, that there are profound philosophical reasons not to be a fan of either of these forms of engineering…
[[Big thanks to Phil Hutchinson for contributing very generously to the researching and writing of this piece, and for our ongoing joint work on 'evidence-based medicine'. Thanks also to Nassim N. Taleb for his influence on my thinking in this area, through the dialogue we are having on it and the arguments we are making against others over it. But responsibility for the piece is mine alone.]]