p.s. Defining 'good' has been a problem for philosophy, see e.g. discussion of Moore's naturalistic fallacy---a problem in trying to define good in terms of something else. Sam Harris' The Moral Landscape has been the most useful book for me on understanding ethics and what good means.
 https://www.britannica.com/topic/naturalistic-fallacy Not sure if that's the best link for the topic, but it's a start.