" weak form of the efficient market hypothesis which states that: future prices cannot be predicted by analyzing prices from the past ..."

No. That is the consequence of the efficient market hypothesis being true. The hypothesis itself is subtly different. Though most people miss it:

All information from past prices is in current prices.

That is a better formulation.

I spent five years studying it and I think it is robust if you remember that it takes time for information to be consumed. That is why HFT works, because it acts before the information can be processed.