The Matrix in 1999 made moviegoers' grey cells work overtime by sneaking in philosophical conundrums under the cover of lots of leather and gongfu.

If that movie got people thinking, the sequel, Reloaded, now showing in cinemas, is brewing more confusion with its brain-bending plot.

Beware: There are spoilers ahead, so for those who have yet to watch the movie, stop now.

Among the multiple questions thrown up by Reloaded are: Why are there six Neos? Who is the Architect? Why must Zion be destroyed? Does that mean Zion is also part of the Matrix?

It all started with Neo taking the red pill instead of the blue pill in the first Matrix.

All of which leads to the most important question: Is all the deep talk just mumbo-jumbo or does it really make sense?

Some moviegoers think the philosophy is pure bunkum.

OVERPOWERING ACTION

MS LIM YI LYN, 26, does not like either Matrix movie. The part-time student, who is doing a masters in deconstruction and post-colonialism at the National University Of Singapore, says: 'It couldn't decide whether it wanted to be an intellectual movie or an action-packed movie. In Reloaded, the action overpowered the plot.'

Civil servant Terence Chua, 32, dismisses it as 'a badly written computer game'. He adds: 'It's a bunch of mismatched pieces of philosophy and theology mixed together and name-dropped in an attempt to make it sound deep.'

The movie's writers-directors, Larry and Andy Wachowski, did base their movies on philosophical ideas.

RASH OF BOOKS

BUT Reloaded tries to cram more than 2,000 years worth of philosophical musings into two hours and 20 minutes of screen time. No wonder cinemagoers' heads hurt at the end of it.

This explains why the movie has inspired a rash of books exploring its themes and implications. These include The Matrix And Philosophy, edited by William Irwin (Open Court); Taking The Red Pill, edited by Glenn Yeffeth (Benbella Books); and Exploring The Matrix, edited by Karen Haber (St. Martin's Press).

Even the movie's official website (whatisthematrix.warnerbros.com/rl_cmp/new_phil_main.html) boasts a collection of papers written by academics. But it is not as complicated as it seems.

The world of the Matrix owes a great deal to French postmodernist philosopher Jean Baudrillard. In the 1970s, he wrote a book of essays called Simulacra And Simulation.

In the first movie, a leather-bound book Neo uses to hide computer disks is titled Simulacra And Simulation.

In his book, Baudrillard posits that because of modern technology and capitalism, nothing is real anymore. He cites Disneyland as an example of an imaginary world that presents as real something that is not. And he argues that Los Angeles is just as fantastical a world as Disneyland.

For Baudrillard, 'the very definition of the real has become that of which is possible to give an equivalent reproduction'. In other words, there is no real thing, there is just the simulation of it.

His theory is just one spin-off of a question which has long intrigued philosophers: How do you tell what is real?

Several famous hypotheses along these lines have been posed by philosophers through the ages.

The first theory is Plato's famous cave story in The Republic. The Greek philosopher, born in 427 BC, painted a scenario in which people were prisoners in a cave.

Born in the cave, they are chained by the neck, hands and legs. They do not know that they are prisoners because they have known nothing else.

They can only see shadows on the walls, but not the objects that cast them. Their reality is circumscribed by their experience, which is deceptive and does not reflect the real world.

The world of the cave is, of course, comparable to the world of the Matrix which keeps its humans in thrall as passive energy sources for machines.

As IT professional Chester Kang, 32, who is intrigued by Reloaded's philosophical musings, says: 'The Matrix asks questions like what is real and who are we. These are things you think about.'

Another famous 'what you know is not real' question was posed by 16th century French philosopher Rene Descartes. The father of scepticism and defender of scientific rationality, in his Meditations On First Philosophy, declared his intention to suspend every belief that could be questioned.

Even a belief in the senses could be fallible as the senses can be deceived.

He asked, what if a 'malicious demon of the utmost power and cunning has employed all his energies in order to deceive me'? This demon, he argued, could mislead people about everything they perceive in the world around them.

Two other philosophers have updated this evil demon argument for the 20th century.

Peter Unger substituted an evil scientist for the evil demon. In his 1975 book, Ignorance, he suggested that the world was just an elaborate deception planned by a scientist who has people hooked up to electrodes run by a computer.

And Hilary Putnam's 1984 essay in Reason, Truth And History begins by asking readers to imagine that they are simply brains in a vat.

The Matrix's scene of people in tubs of pink goo is practically a straight steal from Putnam's scenario.

But what, you may ask, is the point of all this?

Nothing really. For 99.9 per cent of the moviegoers, The Matrix will remain a cool summer blockbuster tarted up with some incomprehensible mumbo jumbo.

But for the 0.1 per cent who care, the movies are an intriguing reminder of eternal questions about humanity's struggle to understand the world and its place in it.

In other words, red pill or blue pill? You choose.