You have decided that you want a revolution to overthrow capitalism. You turn up at a protest or left wing rally and are confronted with a barrage of different socialist publications and organisations you can join.
With this welter of different groups, some with only a handful of members, it is hard to disagree with Tony Benn when he says, 'The problem is, there are too many socialist parties and not enough socialists.'
Forging unity is an important goal for a revolutionary socialist organisation. The reason for such a party's existence is to engage with the living struggles of the working class, which provide the real basis for challenging capitalism.
Those struggles are more likely to succeed if they win the maximum possible unity among workers. Indeed workers can only hope to match the power of their rulers when they act collectively.
So surely the same is true of the parties that workers might support. Failure to unite can only be an example of 'sectarianism' – a term often levelled at revolutionary groups.
But it is not necessarily so. Until 1914 most serious socialists believed that there should be one left party in each country, linked through an organisation known as the International.
Then, with the outbreak of the First World War, many socialist parties threw their lot in with their ruling class to support the slaughter of workers from other nations.
Unity was shattered because some socialists were committed to defending the internationalism of the workers' movement and others were not. There was nothing 'sectarian' about taking a stand against the First World War.
The split was permanent because it reflected the emergence of two distinct currents within the socialist movement.
The first, made up of organisations such as the Labour Party in Britain, aimed to improve workers' conditions by reforming capitalism. The second was committed to organising for the overthrow of the system by the workers themselves.
Despite this, the goal of workers' unity remains important. It is not enough for revolutionary socialists to forge themselves into a party with a distinct vision of how to change the world. They also have to build a bridge to the mass of workers who might still have faith in parties such as Labour.
This bridge between the revolutionary party and the wider working class can only be forged through common struggles. The real problems of 'sectarianism' arise when revolutionaries are cut off from these struggles.
Consider a group of 20 isolated socialists that claims to be the 'world party of socialism', capable of leading workers once they 'wake up' and embrace the truth.
Splitting into two groups of ten socialists would hardly be a disaster. They will be irrelevant to the working class either way.
The stakes are far higher for a party of thousands in daily interaction with tens of thousands of workers – or even a much smaller group that is determined to achieve this.
Similarly, if you build a party around some special revealed truth, it is easy to split once a member of the group puts forward a different version of the truth.
As Marx wrote, 'The sect sees the justification for its existence and its point of honour not in what it has in common with the class movement but the particular shibboleth that distinguishes it from the movement.'
A serious revolutionary organisation starts from what unites it with workers who are fighting back.
And it accepts that while there must be unanimity in the party on questions of principle, such as opposition to racism and sexism, there will be arguments over strategy and tactics as members attempt to relate to different struggles in varied circumstances.
It is fine for a party to contain some members who disagree with the majority, provided they act alongside the majority once a decision is reached.
So which party should you join? The one least interested in petty squabbling on the left and most capable of engaging with the struggles of those fighting back.
The Socialist Workers Party may disagree with other left groups, but it does not churn out tracts denouncing their sins. Nor does it look for blemishes in every movement simply to justify standing aloof from it.
It is only once you get stuck into the struggle that real political debate about the way forward, rather than sectarian lecturing, can be on the agenda.