An interface is humane if it is responsive to human needs and considerate to human frailties.
Jef Raskin, The Humane Interface, 2000 

I've only just turned to chapter four but the first three chapters provided salient reminders of interaction design. Mostly relating to human pyschology human cognetics and consciousness - up to this point - key learnings stand towering over the text.

Even though Jef spends more-than-the-required time to hammer his points he leaves me (the reader) feeling more than satisfied with his 'validating' stories and ancedotes.

FocusLocus of attention

Unlike focussing attention locus of attention deals with the small issue of semantics and object over action. The word 'focus' can be confused with the verb - the act of focussing - whereas interaction designers should be cognizant of maintaining user attention and reducing cognitive load.

Raskin writes that the word locus to mean place, or site. However, to better understand how a user's attention is utilised, concentrating on design that supports short term memory and reduced effort will result in better allocation of the user's cognitive resources.

Before I reached the end of chapter three, positive monotomy, affordances, modes and common level of ability are areas Raskin touches on, which I found really interesting and certainly worth exploring and re-exploring further.

Right, Quantification (chapter four) beckons. Bye.