Radio Times

Over the last half-century, science fiction has provided us with a plethora of well-worn themes and ideas. Some speak to life's big questions - religion, mortality, humanity - some reflect the concerns of the era that produced them, and others are just lovely, silly fun. Paul Jones chooses a few of his favourites.

Aliens

• Aliens do not understand the human concept of "love", yet they are fascinated by it - especially the voluptuous female ones.

• There is something fundamentally inferior about alien DNA: they are obsessed with combining it with human DNA.

• The powerful energy being tormenting the starship crew is really just a spiteful child. It will end up being scolded by its hyper-intelligent pan-dimensional parents and told to come in for its tea.

The captain

• A starship captain is one of the most alluring beings in the universe - no matter what species you are.

• The captain is a huge admirer of the "golden age" of classical music and literature. In his cabin you'll find a number of Tolstoy first editions, as well as antiques from the era, probably including a flintlock pistol.

• He also harbours a desire to captain a real sailing vessel. Give him a holo-deck and it's the first fantasy he'll play out (well maybe the second, after the one about that blonde nurse from sickbay).

• At some stage in his career, a starship captain can expect to be put on trial for the sins of humanity. He'll convince the alien jury that mankind has redeeming features by offering to sacrifice himself to save one of his crew.

• When beaming down to an unexplored planet, the captain will lead a party comprising his most senior crew members. His first officer, top medic and chief engineer must all go along, ensuring that if the expedition ends in tragedy, the ship will be left in the hands of a bunch of civil servants who couldn't programme a transporter to save their lives.

Technology

• A beam from a laser gun always takes a quick x-ray of the victim before it kills them.

• Today, we use crystals to make digital watches work. In the future, they'll power entire starships.

• "Reversing the polarity" is the solution to virtually every engineering crisis. It's the futuristic equivalent of "turning it off and on again".

• Androids yearn to be human and will strive to understand the ineffable "soul". They're also fascinated, and confounded, by our illogical use of language. When on the receiving end of a vulgar insult, a puzzled robot will claim "But that is a physically impossible act".

Future Earth

• In the future, individuality, creativity and sex will be outlawed - and suppressed by a daily dose of drugs - while overpopulation will be solved by enforced euthanasia.

Or…only heavy-metal fans will survive the apocalypse.

• When it comes to space travel, humans have a terrible sense of direction. They'll leave Earth, then spend millennia trying to find their way back…

If the original travelling party agrees to let a new character join their group in the middle of the episode, the new character will die by the end of the episode- normally they die while saving the original group- and are therefore unable to join them.

If only someone would yell at unknown crew-members on away missions - "quick, say something before it's too late", but they never do (even when spoken to) and invariably the unknown crew-member is the first to die.

Any alien civilisation can exist for thousands of years in ignorant bliss, but once the humans arrive and point out the error of their ways, they rise up, overthrow the ruling bodies, thus losing their entire way of life. So much for the rule about interfering - they always do.

The tightness of alien clothing depends on chest size - male or female. So does the neckline.

"• In the future, individuality, creativity and sex will be outlawed"

PFFT!

Any intergalactic federation of planets will have a human president.

All alien races, no matter how alien, will be able to have half-human hybrid children with humans.

All scientific research stations will have an emergency that could wipe out the whole galaxy as soon as the starship arrives. (Solution: don't visit scientific research stations in starships!)

A major concern for people in the future is to ensure that the balance of power in the quadrant doesn't shift.

The most developed region of a newly discovered planet is almost always in the northern hemisphere.

Enemy footsoldiers are bad marksmen rarely hitting the principle characters, and when hit once by the heroes they are immediently killed, whereas the "good-guys" can often survive massive injuries whilst still firing.

Upon encountering an unstoppably destructive alien, scientists will secretly try to turn it into a weapon.

It turns out that a slightly more peaceful and less greedy version of our current society (which is what we'll have after the big war) is better than any society you'll encounter anywhere in the universe. Superior societies do exist, but are peopled by beings so advanced that our feeble minds are incapable of comprehending them. When they do appear to us, they do so in the form of smugger, more self-righteous versions of ourselves.

Apparently superior societies turn out to be subtly totalitarian in a way that only a human starship captian can see.

Being more human is always a good thing even though we are incredibly violent.

Most famous people have encountered time-travellers at some point in their lives.

You have no way of knowing if you're an android or if you're living inside a computer simulation.

Clunky electronics and primitive computer graphics make a big comeback in the future. It turns out, unlabled LEDs and switches are the ultimate user-interface.

Don't forget the HORRENDOUSLY naff-awful 100% synthetic clothing - most spaceships are a laundy fire disaster waiting to happen.

How about: Any footsoldier introduced whom we have never seen before in the show, when sent to accompany a mission, will not live beyond the first third of the episode?

Aliens and/or robots have trouble coming to terms with the concept of emotions - "But captain, why do your eyes leak water?"

Translation devices will not only convert the language of any visiting alien into English, they will also alter their lip movements.

In the future, computers are built to explode in a shower of sparks at any hint of system failure.

All future civilisations are far more militaristic and war-like than our present time.

You can guarantee the death of the people if you haven't seen them in any of the travelling party in previous episodes.

Cliche number 5,003: the future holds a period of industrialised warfare, followed by a period where we'll all live together and live as one race, or just wear white.

In 45 min you can spot a planet, "park" in an orbit around it, beam down, create a problem by you being there, solve the problem, and leave again. Meanwhile, here on earth, it can take you as the same amount of time for you to get to the end of the queue at a supermarket!

No planet in the future - Earth or otherwise - will be made up of nations. Instead, each planet has a single ruler (and often a single outfit). Luckily, all visitors and explorers will land on or beam down to the planet within handy walking distance of the global leader.

Women never have much personality in the future. They usually just simper a lot and fawn after one of the heroes or are very cruel and militaristic, depending on whether they have blonde or dark hair.

All members of an alien race have the same character traits. They are either all ruthless, all militaristic and bound by honour, all smarmy and untrustworthy or all godly and peaceful.

There are no fluffy duvets and soft beds in the future. Everyone lies on a block covered in bubble wrap, facing the ceiling.

Time travellers always arrive in time to witness some important event. Visitors arriving at 30AD will invariably witness the crucifixion, and never just some bloke quietly ploughing his field three months later.

When a truly peaceful alien race comes to our world with scientific knowledge to increase our capacities in space travel and medicine (curing cancer being number 1), they will be met with tanks and guns. Probably they will be shot whilst giving a gift or moving close to someone in a senior role, by a nervous redneck recruit, sparking the war the Earthlings were really thinking would come.

All well established lead sci-fi characters will at some point get to meet a version of them self that happens to be evil.

Not really sci-fi cliches - just Star Trek ones:

The future is either very clean and sunny or untidy and raining.

Planets tend to have one climate (ice world - jungle).

No-one farts/burps in space.