I’m not sure where to send this feedback, so I’ll post it here. It would be easier to provide feedback if the PDF had page numbers and section numbering. I’m using the December 10, 2019 revision.
In the section Temporal Memory Algorithm Steps:
“If the cell is active due to lateral connections to other nearby cells we say it is in the ‘predictive state’ (Fig. 3).” is misleading, it is tempting to imagine that the cells in “predictive state” are active based on this sentence.
“Figure 3 At any point in time, some cells in an HTM layer will be active due to feed-forward input (shown in light gray). Other cells that receive lateral input from active cells will be in a predictive state (shown in dark gray).” this figure is confusing because it shows an arrow to the Next Level as if the predictive information is available to the next level.
“The cells activated by connections within the layer constitute a prediction of what is likely to happen next.” is misleading because the cells are not “activated” in the sense of being “active” they are instead put into a predictive state and the cell is not active.
I had assumed that prediction still had the same meaning as in On Intelligence "Prediction means that the neurons involved in sensing your door become active in advance of them actually receiving sensory input.” but this would need to be changed to align with BAMI e.g. "Prediction means that the neurons involved in sensing your door have an internal predictive state in advance of them actually receiving sensory input.” This is a radical change because the predictive information is not available to other cells. HTM has shifted from being a predictive framework in On Intelligence to a reactive framework (from BAMI "The resulting set of active cells is the representation of the input in the context of prior input.”)
Funnily enough, On Intelligence is providing an argument for why HTM as implemented is not going to lead to “true” machine intelligence. Jeff has said that he does not see any major differences in the framework described in On Intelligence and the current work. Shifting from a predictive to a reactive framework is a fundamental difference.