I'm dismayed nobody else has commented, even in the discussion area.
It's an interesting series. You get to see a subset of Britain's scientists over the last few centuries, who made their discoveries by thinking, by experiment, by luck, and then some applied these discoveries to inventions.
Occasionally going slightly beyond their science, the stories of their lives (just touched on) are also interesting, particularly Newton, Hooke, and Turing.
Although I do have some problems with the series, which I'll describe below, it is certainly worth watching.
The major flaw with the series is its arbitrary focus on Britain. It all seems a little bit like national propaganda. While individual scientists may be patriotic, science itself is not about nationality (except perhaps the social sciences, and of course in funding). Even within the series, pure British science doesn't always happen, with involvement from scientists in other countries. This would have been a better series had it placed these scientists in context with the rest of the world. If the intent was to show Britain as one of the special places where science happened on a larger scale than other places, it should have delved into why.
Another flaw of this series (and frankly most science series I see on TV) is that it barely scratches the surface. It's kind of science porn, with precious little substance. Science is no trivial matter, and if an equation is beautiful, we ought to be given the chance to understand why. A good part of science is about explaining your ideas in simple terms, abstracting out the important bits and presenting them in convincing ways. This series didn't do that. I can't stress the importance of this enough, as science seeks to reclaim significance drained away by non-science.
Also while Stephen Hawking is certainly in the same league as the other scientists covered, I think it's unseemly to have him both host the show, and be included as a subject, and then be interviewed. Also, it kind of morbidly suggests that not too long from now, he'll be as dead and buried as the rest. It may be true, but it's a bit of a downer.
I'd be interested in a series that spent a full hour of each of these individuals, their contemporaries, competitors, times, and achievements, with more focus on the actual science. Going back to Turing, a Turing machine is such a simple concept, but leads to great complexity. Instead of stating it, show us.
My final criticism is that science is presented as obviously a good thing. As someone with a science degree, I remain unconvinced. Science has enabled us to do more and greater things. But IS that good? Science has enabled us to be a lethal danger to ourselves on a planetary scale, and we may have already pulled the trigger with synthetic toxins in the food chain, and with global warming, not to mention the more obvious threat from nuclear weapons. Any science show that fails to address this is not being fully honest.
7/10
