Last month, more than 300 leading European scientists met in Paris to discuss how to spend Euro1 billion (HK$10.92 billion). There were three projects on their agenda. They were: the International X-ray Observatory to explore what happens near black holes; the Laser Interferometer Space Antenna to study gravitational waves; and the Europa Jupiter System Mission to investigate Jupiter's moons. Such missions involve huge amounts of money, manpower and time. Yet none of them would actually benefit mankind. People generally agree that science can help us understand more about our world. This leads to improved technology and living standards and helps us solve practical problems, they say. So it is interesting to note that almost all prominent scientific ventures in the past have been of little practical use. For example, getting Neil Armstrong to plant a flag on the moon cost the United States US$1.75 billion. The Apollo 11 mission served no apparent purpose other than it gave the US a chance to flex its muscles on the international stage and get the upper hand over its fierce rival, the Soviet Union. Another example is the US$9 billion Large Hadron Collider, which will look for a massive elementary particle called the Higgs Boson that will (hopefully) reveal more about the nature of dark matter. Unfortunately, finding out more about the fundamental laws of the universe will not save lives or improve our quality of life. Billions of dollars have been spent on scientific research involving telescopes built on top of mountains and detectors buried hundreds of metres beneath the Arctic ice cap. Again, none serve any meaningful purpose in our daily lives. Wouldn't the time, resources and manpower be better spent on more pressing and practical issues, such as stem-cell research or improving communications? So what really is the purpose of science? Does it benefit humans or does it simply satisfy our curiosity? And are scientific research and space projects futile as they seem? Looking back, most great inventions and scientific theories began as just curiosities. When Michael Faraday discovered electromagnetism, he had no idea it would one day be central to almost every electronic device in the world. Nobody would have guessed the importance of radiation in carbon dating and radiotherapy. Missions to the moon may seem to have no practical use but they led to inventions such as velcro, enriched baby food, freeze drying, water purification and solar energy. We cannot tell what will come out of Europe's next space project, but we can expect that something, somewhere will somehow bring benefits to mankind someday.