No, it is not possible. The Age of Enlightenment (18C) produced a good many polymaths who were the nearest to that ideal, but only because the contemporary range of knowledge in each science or philosophy was sufficiently limited for such people to learn most of it.
Nowadays the total range and depth of knowledge is so great nobody could possibly know it "all", even within their specific disciplines.
I dunno Durdle. I know a few people who seem to know an awful lot about an awful lot. I ask any question on any subject and they know a little something about it! One long-time friend in particular. A very smart guy and he reads a lot. But he always amazes me. He sometimes know IN DEPTH about the subject and sometimes just a little bit. But I cannot recall a single time when I asked a question of him that he said "I have never heard of it" or "I don't know a thing about it". He's not a smart aleck or arrogant at all. He just is what he is. A very wide-range of knowledge. There are probably more folks like him. Curious, well-read, knowledgeable. Thank you for your reply Durdle! :)
An interesting person to know then, your friend. Oh yes, I am sure there are many like him, with a very wide general knowledge, but there will still be limits to what they know.
The way that scientists and engineers approach having to understand their fields very deeply is not to try to memorise every detail, but to understand the principles and the mental and physical tools of their trade, together with knowing where to find the necessary information to help them solve the problem of the day. They build up libraries of text-books and learned-journals containing, say, the mathematical formulae or the tables of characteristics of materials, and know how to search them efficiently.
Humam memory is not infallible, even among the really knowledgeable, and I remember an e-soldier passing on advice his sargeant had given him when learning to maintain vehicles.
The NCO had said, "Never try to remember things like tyre pressures and engine adjustments. Always remember where to find them!" (In the driver's or workshop handbooks.) "Otherwise one day you'll forget, or muddle up two vehicles, or the manufacturer will have changed them, and you'll end up with a vehicle we can't use!"
Perhaps the moral there is the difference between knowledge and wisdom.
I have a friend who is amazingly intelligent. He was reading at age two, and his IQ is the highest in the history of his high school. He learns many things amazingly rapidly, and that has resulted in very quick promotions and big raises in his employment. He can glance at a letter about three seconds and repeat every word on it precisely. He reads phenomenally rapidly and remembers every word he read. He also has amazing physical abilities. He is so quick that electronic tests can fail to even register. He lifts more than his father and brother combined. He has won black belts in martial arts in record time.
Durdle 