The Lenses concept is central to the book, most chapters revolving around one or two of those lenses.
Each lens is a conceptual approach to look at your game, and explore its qualities and deficiencies.
For example, #14 The Lens of the Problem Statement
And straight from the book, these are the questions asked by this particular lens.
What problem is your game a solution to ?
Have I been making assumptions about the game that have nothing to do with its purpose
Is a game really the best solution? Why?
How will I tell if the problem is solved?
I believe all the various lenses are on the Deck of Lenses website linked in the original post.
Back to reading,
Cheers !
