There's been a few articles on the topic recently. Funnily enough, two of them are around the same time and with basically the same title - this must be on people's minds these days.
Are you about to graduate and deciding whether to join a startup or a larger company?
If so, you may want to read these three articles. Two of them outline reasons to join a startup, and one of them outlines reasons not to join a startup.
As for my opinion, I think that if you're determined to start a company in the future, then joining the right startup is the smart move. It will accelerate your learning by years. You might even consider starting your own business right away - though you should definitely count on the high probability that no matter how certain you are of your success, your first X businesses (where X is between 1 and 5, but almost certainly not 0) will probably fail in some way or another.
If you're not entirely convinced, you may find that having a big company on your CV gives you a bit more security, and more time to make up your mind. It will reduce your risk a fair bit, at the cost of a few more years. You will learn a lot in large companies too, by the way - startups are not the sole keepers of useful business knowledge.
There are plenty of startup founders who started off working for large companies, so you'll be in good company whichever path you choose.
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