Image caption What would Kant say to social climbers?

Getting on in the world is a priority for many. But is social mobility good? As the BBC researches the class system, philosopher Mark Vernon says thinkers like Kant have mulled over such questions for centuries.

Is social mobility good? The immediate response would be yes, of course.

Who could argue against lifting people out of poverty, rewarding individuals according to merit, and ensuring equal opportunities for all? Surely, a more socially mobile world is a more just world.

This is why BBC Lab UK has devised a class survey to test if the traditional class divisions still apply.

The moral upside of social mobility is particularly clear in a Kantian approach to ethics.

German philosopher Immanuel Kant was very clear that an enlightened culture is one that does not rely on inherited traditions, authorities and social structures. To be enlightened is to question and challenge such aristocracies, be they aristocracies of wealth, politics or the church. Social enlightenment brings justice in its wake.

Which class are you? The class test takes about 25 minutes

Covers wealth and job type, as well as interests and social circle

Aims to find out if traditional divisions of working, middle and upper still apply Take the Great British Class Survey More tests from BBC Lab UK

It also enables the individual to take responsibility for their own lives, and not be weighed down by cultural constraints. It's the kind of justice that spreads freedom throughout society, based on just deserts rather than birthright.

But there's a price to pay for social mobility that other ways of looking at ethics highlight.

The utilitarian approach to life, associated with philosopher Jeremy Bentham, always returns to a single question - what makes for more happiness in the world?

Does social mobility achieve that? Well, it might.

But social mobility also produces dislocation. People migrate to cities and find themselves isolated from their family, and constantly having to make new friends - relationships that might be fun but not very deep. They may be richer, but are they happier?

The new meritocracy

There's another problem. In a socially mobile world, life's rewards are no longer the preserve of elites, but are distributed according to merit.

So what happens if you feel you don't receive your fair share of life's rewards? You've now only got yourself to blame. In an elitist world, you could blame your birth. In a socially mobile world, what you get is more likely to be thought of as what you deserve.

There's another concern. It's raised by the third approach to justice, that of virtue ethics, associated with Aristotle.

The virtue ethicist would want to ask whether a socially mobile world rewards certain kinds of ability more than others. For example, someone with skills in banking or sales can do pretty well in a market society such as ours. But someone with skills as an artist or a mother may well find it hard to make ends meet.

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Further, the virtue ethicist asks, does a socially mobile world actually undermine certain roles that are great goods - such as the arts or being a mother?

These things contribute to the common good. They are part of any just, flourishing society. And yet, social mobility may sideline them by not appreciating them.

This is not to say that a virtue ethics approach is against mobility.

What it would suggest, though, is that a good society needs to have ways of rewarding individuals that contribute things of moral, not just material, worth.

That might be a society which funds the arts, encourages the humanities as well as sciences, and doesn't forget that what goes on in the home matters at least as much as what goes on in the marketplace.

Mark Vernon, the author of Philosophy For The Curious and Ethics For The Curious, will tackle more modern dilemmas throughout the week. Tomorrow, should victims have a say in sentencing criminals?