I 100% agree with your comment however in regards to it's relationship to the parent comment I have to disagree somewhat in the usual nitpicky hackernews fashion:
Asking someone to draw "a bicycle" is different to asking them to draw a specific bicycle or a functional bicycle. Also what does it mean to "know something"?
If you ask someone to draw a house and they draw a square with an overhanging equilateral triangle centred on top, it's not that they don't know what a house is. That's just a symbol representation of their own personal definition of a house.
The equivalent here would be if you drew that same stick-figure house but put the door adjacent to the roof rather than the floor, or the triangular roof along one side rather than opposite the ground.
Asking someone to draw "a bicycle" is different to asking them to draw a specific bicycle or a functional bicycle. Also what does it mean to "know something"?
If you ask someone to draw a house and they draw a square with an overhanging equilateral triangle centred on top, it's not that they don't know what a house is. That's just a symbol representation of their own personal definition of a house.