THE PHILOSOPHER, Jeremy Bentham, said governments would succeed if they set out to deliver 'the greatest happiness, for the greatest number'. This view emerged in the late 1700s, and as Brexit becomes more real, with the date when we will actually leave the EU now set, the government is under increasing pressure to deliver that greatest happiness concept.

We now know that the transition period will end on December 31, 2020. By then we will need to have arrangements in place if we are to continue trading with the EU, a support structure to maintain farm support and rural development funding.

There is also a long list of other things needed to take over tasks for which the EU has been responsible for many years. Those range from product licensing through cooperation in human and animal health to food promotion, where we will be in competition with an EU that is increasingly aggressive in marketing food around the globe.

Getting those right will be the key to delivering 'the greatest happiness'. One risk for farmers lies in the reality that what governments want is indeed a good outcome for the greatest number.

The food industry has given a guarded welcome to the deal struck between Brussels and London. They would have liked a longer transition than 21 months, but with that set it does at least give the industry an immovable target around which it will have to work. In return it needs assurances from Westminster that it will finally stop playing political football, and get on with the game. As things stand, the government has many parallels with the Six Nations English rugby team that talked a great game before the championship started, had a coach that insulted other countries – but ended up one step from the bottom of the results table.

The message from the farming and food industry is simple. They are not interested in politics, but want to know how the government is going to make this work, and how it will maintain the 70% of our export trade that goes into the EU-27. These are real decisions for the real world, and not knockabout politics for those who believe leaving the EU will in itself forge a successful economic future. That can happen, but it will not be an automatic process. It needs to be driven through good deals. The biggest political challenge will be the Irish border, rapidly followed by delivering Brexit without damaging UK devolution.

If we go back to the 'greatest happiness' philosophy, that inevitably means winners and losers. That should be worrying the farming lobby. We have already seen that the prize for the fishing industry of exiting the EU in March will last just a few minutes, before the government accepts EU regulation through the transition. To be blunt, fishing is not sufficiently economically important for the government to deliver on a pre-referendum promise that Brexit would end the Common Fisheries Policy.

That has to remind farmers of the weakness of their position. There are more members of organisations like the RSPB or National Trust than there are farmers in the UK, so a green Brexit will be popular. People's big concern is also with the price of food. Provided that stays low, as it is now, the majority will not mind where food comes from. If major retailers guarantee quality and wholesomeness that will satisfy the majority of people.

A report from the Institute for Fiscal Studies this week underlined the dangers for agriculture in the 'greatest happiness' approach. It says scrapping all import tariffs, and so removing special protection for sectors like agriculture, would have a marginal impact on consumer prices. It suggests increases would be limited to just over 1%.

This is well below the 2% consumer price rises we have seen because of the weakening of sterling. This would be achieved because of increased competition, and for food it is easy to work out that this would be from non-EU-27 imports. This would deliver a good outcome for everyone, apart from those in industries now protected by tariffs. It would deliver the best post-Brexit outcome for society as a whole.

At the time of entry to the then EEC back in the 1970s, Edward Heath reportedly deemed the fisheries industry 'expendable' in the negotiations. Hopefully no-one is saying that about farming at Westminster now.