This year’s Labour Party conference passed a motion, brought by the CWU, calling for the party to support a 32-hour working week. It followed a 2018 report from the TUC, which called for a 4-day week and many unions, including Unite, PCS, and RMT announcing commitments to shorter working hours.

Despite this, much of the current discourse around the 4-day week, often granted more publicity, has been from think tanks, academics and liberal journalism. This set of voices and the tones in which they pronounce the cause can make it is easy for the left to dismiss it as comparatively less radical and indeed urgent than other agendas. But this would be a mistake.

After all, it was Karl Marx who famously stated that the shortening of the working day is the “basic pre-requisite” of freedom. Labour’s policy to move to a 32-hour week is more than just a technical fix to our current economic failings (although it is that); it represents a radical shift in power from capital to labour, the size of which has not been seen for generations.

The wage we earn for a normal working day is ultimately determined by what it costs to sustain ourselves and keep returning to work. Or, in his words, the cost of reproducing our labour. That cost depends heavily on the standard of living and the price of food, clothing, housing; all of which vary by country, region and class.

Variation in supply and demand in specific skills and experience may also increase or decrease some groups’ ability to command wages above the average. But, in the end, capital pays its workers what it must to make sure they come back the next day – and no more.

But, once the wage is set, there is still the matter of what constitutes a normal working day. In a legal, contractual exchange, both the employer and the worker have an equal right to determine what that length should be. “Between equal rights,” Marx wrote, “force decides.”

And so, the battle over the number of working hours considered ‘normal’ becomes a battle between organised capital and organised labour; the fundamental battlefront of class struggle. In a capitalist world where, save for inherited wealth, we are forced to engage in waged work to survive, the accepted limits of working time are the measure of our subjugation to the system.

Beyond theory, the same fact can be demonstrated historically. Among the discourse around Brexit, the EU is often praised for its protection of workers’ rights – but, while it is true that many of our rights are enshrined in EU law, it’s hugely important to remember that they were established by the labour movement. The five-day week, the eight-hour day, paid holiday, sick pay and maternity pay were all instituted by mass movements, trade unions and collective bargaining.

Starting as early as 1802, various iterations of legislation– collectively known as the ‘Factory Acts’ – have been passed in the UK, each proclaiming to protect the rights of workers. The first significant Factory Act, passed in 1833, was undoubtedly a result of the ‘Ten Hour Movement’, one strand of which was the Factory Movement which began with the Cotton Spinner’s Union in Lancashire.

The 1833 act intended to prevent children under the age of nine from working in factories, ensure those under 13 worked no more than eight hours a day and those under 18 no more than twelve. However, in reality, the fact that the legislation only required four Factory Inspectors for the entire country meant that these laws were largely unenforced.

This failure followed quickly after the Reform act of 1832, dubbed as the ‘great betrayal’ by workers, because it extended the right to vote but only to property owners. The combination of these two events led to the rise of Chartism and the growth of trade unions.

Over the next two decades, incremental laws added to and strengthened the rights of workers as they organised and agitated. In what now seems like a strange alliance, the landed aristocracy in Parliament responded to these demands in a bid to keep power from the ascendant bourgeois industrial class.

However, the laws were consistently ignored and frustrated by factory owners until in 1850 the sheer scale of class antagonism led to the ‘Compromise Act’. This act slightly extended the length of the week, but, as a result of pressure from workers, the industrialists finally agreed to enact the laws.

The eventual legalisation of Trade Unions in 1872, and notably, Eleanor Marx co-founding the GMB in 1889 with the eight-hour day as a core objective, led to a continuing series of gains, not just in shorter working hours but for paid holiday, sick pay and maternity leave. These advances were undoubtedly made easier by the realisation that the health benefits of having enough time to eat and rest properly meant overall output barely changed.

Working hours reduced steadily in the UK until the 1980s when successive Trade Union Acts, passed by Thatcher, Major and Cameron, severely hindered the possibility of industrial action. When the UK’s working hours effectively levelled off, other European countries which protected their Unions, such as France and Germany, have continued their steady decrease.

The 32-hour week motion brought to Labour conference by the CWU follows their successful negotiation, in 2018, to implement a 35-hour week by 2021. Their ‘Drive for 35’ took the same name as the CSEU’s campaign in the early ’90s, which achieved a 37-hour week. These instances show that, even though they have been attacked by burdensome requirements for striking, the struggle over working time has never left the trade union movement.

Limitations on the working hours of adult males have, in fact, never been regulated in the UK. Many of the rights workers have taken for granted until very recently were maintained by collective agreement. The European Working Time Directive does not protect a five-day or even 40-hour week but, in fact, imposes a 48-hour limit. Even then, an opt-out clause has always made it technically possible to work any length of hours.

However, for a long time, a ‘standard’ working week has been upheld by consensus. A decade of austerity, the rise of the gig economy and zero hour contracts, and attacks on the trade union movement have left that consensus in tatters. What counts as a ‘normal’ working day is no longer secure, and Marx’s writings have become all too relevant once again.

The urgency with which the Labour Party are now fighting for our workplace rights is in part a reflection of the constraints imposed upon the union movement which originally won them. For this reason, it is absolutely right that when John McDonnell announced Labour’s plans to move to a 32-hour week at this year’s conference, he was clear that the primary mechanism to achieve this would be freeing the unions to engage in collective bargaining once more.

In the coming months and years, the Labour Party will enter government and be forced to institute – and prioritise – the myriad elements of their political programme. The move to a 32-hour week mustn’t be seen by the left as a nicety dreamt up by policy wonks, but as an essential means to loosen the grip of capitalism and a necessary foundation of a socialist agenda.