Quite -- but even if not, then I think kuiperbelt's comment is also too fixated on sustained life, or complex life -- or, at the very least, on life still existing today. It's possible for example that life of some form was present on Venus, say, early in its history, before the current conditions took over. Granted, establishing this one way or another is particularly difficult on Venus, but even still, four billion years is a long time, and you only need habitable conditions on the planet for, say, a few tens of millions of years (which is thought plausible, see eg
http://www.nasa.gov/feature/goddard/2016/nasa-climate-modeling-suggests-venus-may-have-been-habitable ), for some form of basic life to have emerged.
At the other end, one can arguably exaggerate the role the Sun plays in sustaining life (in terms of distance, light etc) -- it's difficult to see how relevant the Sun is, for example, to sustaining life found at the bottom of the Ocean, where its light doesn't penetrate and so its influence is at most indirectly felt; likewise, the existence of the "deep biosphere", which is to say life that exists well below the surface of the Earth's crust, is also pretty evidently free of the Sun's influence.
All of this means, in effect, that even on Earth the conditions required to maintain life in some form are not actually that tightly constrained. So, not only do you have Naomi's point that maybe there are other conditions beyond our planet in which life could emerge, but you also have solid evidence that it can exploit all sorts of conditions -- from low to high temperatures, from low to high pressures, with little available water or lots of it, with a lot of oxygen or none at all, with abundant energy sources or with the bare minimum, etc etc.
This isn't to say that life can emerge literally everywhere, or can maintain itself indefinitely regardless of the conditions or what changes may occur, but I *do* think it says that one should take seriously the idea that life can emerge on other planets, or other moons, in the Solar system. There is, for example, plenty of water on Enceladus, or Europa, or Titan -- also the only moon in our solar system with a significant atmosphere. There are apparently many other moons of interest, too numerous to mention, and while some of this may be wishful thinking, there's enough interest that several missions have already been funded over just the coming decade to visit a few of these places.
Even if those missions find nothing, or nothing concrete, it seems worth looking.