Stop thinking ourselves? No, but just humbly consider that that flash of insight you may have just had might have been considered, named, and much more eloquently stated hundreds of years ago.
This thread would have people stop writing things on the Internet altogether, unless they have approached it the way one approaches writing an academic paper for peer review.
There's a value in writing down that flash of insight, even if it "have been considered, named, and much more eloquently stated hundreds of years ago".
For one, nobody can be familiar with all that "has been considered, named, and much more eloquently stated hundreds of years ago". Especially if it's not their main domain or main hobby.
Second, an amateur stumbling with his insights might also come at an interesting insight once in a while.
Third, it doesn't preclude anyone from going to the "real" experts. If anything, by discussing such things, it makes it more possible.
The only problem would be if said amateur thought he had the answers and that all the experts or previous discussion were wrong (like people who claim they have invented the perpetual motion machine, etc).
But I don't think we have that here.