But let us find out. How do you define spam, and why should anyone take that definition seriously?
My definition of spam is when someone doesn't transact because they want to make an economic transaction, but rather to do something else, like filling blocks with crap or bloating the blockchain.
Alex, have you ever written any code?
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Please tell me you understand, and that I don't need to resort to lower, register-level explanations.
Yes, I have. Starting with zx spectrum basic in the 80s and leading to assembly on PCs in the 90s.
However trying to understand the intent by code is unnecessary. You can see it and patch it in some cases (like dust movement), but it can be fooled with larger amounts. Anyway, the primary way to deal with the issue is simple: Fees. That's what all altcoins do when they get attacked. Raise fees. That's what the practice shows. The miners will typically transact anything that comes their way because they follow the system's rules. If the system hasn't the proper disincentives in place, in a way, it's not their fault.