"If you can see a bubble happening, then it will cease to be a bubble." This statement is over-simplified. Let's talk real-estate speculation for a minute. You

"If you can see a bubble happening, then it will cease to be a bubble." This statement is over-simplified. Let's talk real-estate speculation for a minute. You could be aware that the price you're paying for some property is over-valued, but still take the gamble because you think you'll be able to dump it before the bubble pops. Once awareness reaches a critical mass it may cease to be a bubble, but that doesn't happen overnight.