Another thought provoking article from my favorite marketing guru Seth Godin [bold emphasis mine]
What I discovered, though, was that domain knowledge, edge to edge knowledge of a field, was incredibly valuable. It helped me understand where the edges were, and it gave me the confidence to be selective, to develop a taxonomy, to see what was going on.
As the deluge of information grows and choices continue to widen (there's no way I could even attempt to cover science fiction from scratch today, for example), it's easy to forget the benefits of acquiring this sort of (mostly) complete understanding in a field. I'm not even sure it matters which field you pick.
Expertise is a posture as much as it is a volume of knowledge.
Reading every single trade journal, for example, or understanding the marketing, engineering and sales of your field--there are countless ways to go deep instead of merely paying lip service to the current flavor of the moment.
To me, the importance of domain knowledge (specialized) is especially relevant for those in the financial markets (or in stock markets).
Instead of acquiring the necessary ‘signals’ that could deliver the ‘edge to edge knowledge’, most get lost in the din or cacophony of ‘noises’, which Mr. Godin describes as the “current flavor of the moment”.
The latter can be characterized by the pervasive use or application of cognitive biases and logical fallacies, except that they are masqueraded in numerical or technical methodologies which are completely dependent on past or historical activities or on some presupposed constants which operates on aggregated formulas.
Popular or consensus wisdom usually represents what Black Swan theorist and author Nassim Taleb calls as the negative knowledge (wrong and doesn't work).
For many, thus, expertise signify more as social signaling (posturing or seeking social acceptance) and or “telling people what they want to hear” but predicated on certain technically based paradigms which produces an aura of supposed superiority rather than representative of the true domain knowledge.
We should learn how to separate the proverbial “wheat from the chaff”