I follow Ryan Holiday and Shane Parrish and they say to read a lot. Read everything. Read everything you can get your hands on.
Then, Seneca says to not read many books, but stick with a few and know them well.
Take notes, keep a “commonplace book” for the wisdom you gain from reading.
Then, Seneca says it is a tragedy for a man's wisdom to be housed in a notebook.
So, what should we do?
Try something.
If it works for you, great! Make an adjustment. If it's better, great! If it doesn’t work for you, try something different.
I think Seneca's point is that quality matters more than quantity. You can read everything, but if you don't internalize it, if you don’t remember it, understand it, it is worthless. Simply memorizing or reciting quotes from somebody else is nothing.
Use what you read, use the people who came before you as a starting point; use them as guides. But as you are walking down the path, if you see a different route, try it. Blaze a new trail.
Make the path your own. Clear the path so others can see and follow it.
Like Seneca says, speak your own message, with authority. No person holds a monopoly on the truth. Be grateful for the wisdom of those who came before, but do not be stuck thinking they have the one and only way.
Figure out what works for you - and then do it