I learnt more about the affordance concept and other principles I was not aware of, now I got them clearer, also how some of them relate to interface design.
About skeuomorphism concept that I forgot for a lot of time, and that the trend of flat design is just that, a trend.
Got a deeper understanding about mental models and the huge importance of perception.
That Nik is passionate about this subject and it would be exiting to learn from him.
Not plagiarize under any circumstance.