They are being incredibly charitable with the width of that column
and also by not showing the bigger picture
https://i.postimg.cc/V19Jwzqd/knowledge-circle.png
there would also be an even bigger boundary of "all of reality" or something but obvs that would be infinite and impossible to know
The ratio is off. You learn a lot more from high school and bachelor's degree and you learn way less with your master. PhD is just expanding a little bit more on master.
The visual is more about highlighting specialization and its distance from the limit of human knowledge. You often can't represent every aspect of a complex subject at the same time on a single visual. Kinda like how you can't represent the solar system distances and planet sizes to scale on a single page, you have to pick one.
Anyone knows the origin of this representation? I've seen a professor use it years ago and I thought it was his, but I guess not.
Source: https://matt.might.net/articles/phd-school-in-pictures/?_nospa=true
People can make dents in the outer shell of human knowledge without having PhDs though. As in to discover something new and revolutionary, plenty of great scientists have and likely many more will continue to.
Or you can just make up a bunch of shit ala Dan Ariely and Francesca Gino.
