The problem is that understanding the economy is probably harder than understanding human intelligence. After all, the global economy is the product of over 6 billion human brains interacting with each other and their environment.
What does 'understanding the economy' mean? Routinely economists point out missed opportunities which the market then exploits (IIRC one of the standard examples was a paper which discovered a small average rise on Mondays), or simple models outperform the economists' predictions of the future.
This is our monthly thread for collecting these little gems and pearls of wisdom, rationality-related quotes you've seen recently, or had stored in your quotesfile for ages, and which might be handy to link to in one of our discussions.