People who lived hundreds or thousands of years before now would have thought that it's impossible to survive a high fever like seen in some malaria cases. Same as many other illnesses today that through science we are able to save many lives which would have been lost if it were in those old days.
It's just a little over a hundred years ago since man took to the sky for the first time. Am talking about the invention of the first airplane in 1903 by the wright brothers, Orville and Wilbur. To most people of that time, it was an overwhelming achievement. To the people before them, it was a complete impossibility. Today, we have space planes or ships like they call which can very well travel beyond our clouds into space. Virgin Atlantic is even starting commercial flights to space by next year. How do you think people from hundreds or even thousands of years ago would react if they were told of this achievement? Unimaginable will be the answer. A vast majority of humans from the old world didn't even think there was space and other planets, they thought heaven was just beyond our clouds. So how would have such people reacted to seen a plane, talk much of a space ship? This is the case with certain people of today who think science can't go beyond what it has achieved today.
Drawing from the above, i think there's really nothing that is not possible with science. I mean, if science was able to bring 3D printers into reality, then nothing is beyond reach. It's only a matter of time. We might not be able to conceive some of these ideas because we think it's impossible. But then, that's exactly how people from previous times thought about most science advancement today. Like I said, it's only a matter of time before many more things are brought to reality through science. I like to think that as long as the human mind and brain is alive and can produce ideas, it will also find ways in bringing those ideas to reality.