I used to believe that you do not need to know everything, that it is sufficient to know where to find it . "A well made rather than a well filled head "
Is that so?
Look at this pad in front of me! It contains a few thousands of the best books in the world, writers, sages, thinkers, legends, myth, fable, proverbs and sayings, sacred writ of great religions, history, philosophy, sculptures, paintings,... and also the best dictionaries, sources of quotes...* The sleeping wisdom of the World...
Here and now, they are (almost as if) all laying in my lap. I posses the books, I have them, well, I have copies of copies of copies of them. Now what, Ioan?
I cannot own them, they are still not mine. They would be mine only after absorbing the marrow of the whole lot in my mind. A child can count on his fingers that in the best of cases I cannot hope enough days left in my life to read this, and even less to assimilate it and make it mine.
In fact, even if the brigand rapacity of the copy right businesses and the censorship of the tyrants and the snooping mania of terrorised governments do not choke the open access to culture on Internet, we still head into a Huxley-world of cheap Television and mystified Internet civilisation where people become unable to read books, in spite of all being available to them. As Neil Postman  wrote, Orwell described a world where people were forbidden to read books, while Huxley drew one in which people will be incapable to read.
Even without gate-keeping and censorship, another monster advances, the deluge of quantity which dilutes the valuable culture in an ocean of rubbish. If you do not know in advance what you seek, you will drown. As if a subtle enemy were working against our passion to know, with a perverse strategy: "If you want to grow it, water it. If you want to kill it, flood it!"
For the young Internauts of humanity this implies, now, a choice between a new kind of education and yet another middle age of illiteracy. This time it will be darkness in full light!
How to prepare for the flood? What to do under the deluge of confusion?
Like legendary Noah, I tried to go back to square one – in haste – to select and take on board only the time-tested great books of humanity. Read them first, I told myself, all the rest can wait; unfortunately, that only works for me in private, such passéism would kill almost everything recent. How sinister it would be to drag humanity back into the past, how unfair to the new creators! There may be something new in this world, after all.
I gained temporary advantages though; from the time I started my cultural fundamentalism strategy, I felt less confused and I learned much quicker, with less spam in my eyes and ears. I feel relatively secure because I see the way and I have a key. A few great books are now mine too.
Gradually, I become more aware from where we come and what my words mean. Definitely, I know today much more about the immensity I do not know. With this I am a little wiser.
Mine, is a strong strategy, for a while.
Seneca the philosopher was more radical, as he limited the choice to conformity:
"...reading of many authors and books of every sort may tend to make you discursive and unsteady. You must linger among a limited number of masterthinkers, and digest their works, if you would derive ideas which shall win firm hold in your mind. Everywhere means nowhere. When a person spends all his time in foreign travel, he ends by having many acquaintances, but no friends...
... So you should always read standard authors; and when you crave a change, fall back upon those whom you read before. Each day acquire something that will fortify you against poverty, against death, indeed against other misfortunes as well; and after you have run over many thoughts, select one to be thoroughly digested that day. This is my own custom; from the many things which I have read, I claim some one part for myself..." 
Another great thinker, Arthur Schopenhauer, has another reason to read selectively by thinking first his own thoughts and reading afterwards to complete them:
"...much reading deprives the mind of all elasticity; it is like keeping a spring continually under pressure. The safest way of having no thoughts of one's own is to take up a book every moment one has nothing else to do. It is this practice which explains why erudition makes most men more stupid and silly than they are by nature, and prevents their writings obtaining any measure of success...
Reading is nothing more than a substitute for thought of one's own. It means putting the mind into leading-strings. The multitude of books serves only to show how many false paths there are, and how widely astray a man may wander if he follows any of them. But he who is guided by his genius, he who thinks for himself, who thinks spontaneously and exactly, possesses the only compass by which he can steer aright. A man should read only when his own thoughts stagnate at their source, which will happen often enough even with the best of minds. " 
The bad solution to the immensity of the past is certainly the current, dominant one: specialise and ignore the rest. This arrogant choice of ignorance is grounded by a blurred belief that – with the progress of science and technology – the old writings grew obsolete and only recent things count. Worst than this technological ideology are only: “We don’t need no education...” or the one-book-culture.
On this narrowing path of tight separation by disciplines we also lost the way of reasoning of the universal genius... We wait, I believe, for new giants of synthetic mind like Aristotle or Leonardo, Montaigne, Shakespeare or Newton, or Einstein, not blinded by technology, method and gain, to turn their genius towards the human condition and culture today.
We have a possibility to trust some recent well read sages to select for us credible lists of books worth reading; they cannot be however technicians alien to the cultural heritage which “does not compute” and certainly they cannot be little-red-book politicians or firm believers of whatever creed.
With this choice there is good company available to join. Great writers use to share what they read and advise what is worth. Some lettered trials are the life-time reading plans of the Western Cannon and the Eastern one:
Harold Bloom proposed the Western literary Canon  Read the books he listed and you will be a cultivated Occidental... and a few years older. For a shorter kind of list, Italo Calvino would probably inspire you 
An Eastern canon is added to the Western, to speak about a meaningful world culture: a trial among several is at Online Literature.
Indeed, how could you speak about culture, without reading sacred writs of the East, like the Koran, Tao te Ching, Confucius, Buddha, Zoroaster, some Upanishads, some Egyptian and Tibetan books of the dead, to complete our Hebrew and Greek roots? How to ignore Gilgamesh, the Persian poets, The Chinese Arts of War, Zen haikus and the oceans of streams of Indian stories from which come many of our tales, fables and dreams?
If you chose this path of following mentors - and you should do it without haste - with some perseverance and while still young enough, you will find plenty of good leads and pleasure, rewarding juicy fruit. You will find even here on Earth, another, richer, world to complete this one, a world in which your mind has more choice and freedom to move.
In the empire of books, we require an education of search for our own voyage.
We need to learn how to chose, how to judge, how to learn and how to forget.
This learning means that you build your own head, an ability to ask questions and to evaluate what you found, to ask: “Really? Who says so?” to say “I like this, but not this.” and “Sorry, this I do not understand.” Such style of learning is built traditionally on being educated by example, in an educated family or by great mentors. For the art of reading you need masters, not teachers. The internet navigator deserves an aristocratic education, not a democratic one, else he will become run-of-the-mill trash carried by digital tides.
To stay clean of litter on our way, we also need a re-education of the quote-culture; most of the rubbish that pollutes the mind on Internet today drips from imbecile attribution of ideas and phrases to people who never said them. By some perversion, it became usual to "quote" boldly, without indicating who and where and when.
To really understand an idea you must know its parents. Keep in mind that a quote quotes!
We also need technology to turn towards content, with tools serving the seeker on the Net but also home. Today, I still do not find the simple decent private search engine which - like Google - would find the paragraph, the phrase, the idea I need, when I need it, not on Internet but here in my lap, on my own computer. The profusion of technicians do not seem to understand yet or care for the usefulness of helping us to find things in our own treasury chest.
Well, this being the disquieting state of the matter it is still true that a voyage of a thousand miles keeps starting with the one next step; any good book is a door to everything else. In spite of my anxious look at all those tomes, it is never too late in fact to start reading a great book, any good book, as a first step.
It was well said that even a little learning, no matter how late in life, is like a small candle lit in the dark. It kindles a warm little nest of light, much friendlier that the chilling darkness of ignorance.
*and I left aside Music and Science and particularly everything else I forgot this day.
 “You don't need to know everything, just know where to find it.”
No, it is not from Einstein, nor an American president! Exact quote with context: “A clergyman should be well equipped for indexing the best he reads in books and for filing clippings. Educated people are not those who know everything, but rather those who know where to find, at a moment's notice, the information they desire..." The Expositor and Current Anecdotes, Volume 16, Indexing and Filing, 1914-1915, [INDEXING AND FILING, Advertisement for Wilson Index Company of Lynn, Massachusetts] Page XX, Column 2, F. M. Barton, Publishing, Cleveland, Ohio. Quotation appears two pages after page 744 on a page labeled XX) This, cf. Quote Investigator to whom I thank again for their work.
Rectification on 3 October 2012: The original source appears to be Samuel Johnson: "Knowledge is of two kinds. We know a subject ourselves, or we know where we can find information upon it. When we enquire into any subject, the first thing we have to do is to know what books have treated of it. This leads us to look at catalogues, and at the backs of books in libraries." — Samuel Johnson (Boswell's Life of Johnson, Ed, A Birrell, Westminster, Archibald Constable and Co, 1896). Thanks to John I. Spouge for looking deeper into the well of the past.
 Explains Montaigne: “ For a child of noble family who seeks learning not for gain (...), or so much for external advantages as for his own, and to enrich and furnish himself inwardly, since I would rather make of him an able man than a learned man, I would also urge that care be taken to choose for him a guide with a well-made rather than a well-filled head; that both these qualities should be required of him, but more particularly character and understanding than learning; and that he should go about his job in a novel way. (my bolding) Michel de Montaigne, Of the education of children, in SELECTED ESSAYS TRANSLATED, AND WITH INTRODUCTION AND NOTES BY DONALD M. FRAME, Classics Club, WALTER J. BLACK, • ROSLYN, N. Y. , 1943
 Postman, Neil, Amusing Ourselves to Death: Public Discourse in the Age of Show Business. USA: Penguin Books, N.Y., 1985. A book to read carefully, I am afraid. The exact quote from the Introduction: “Orwell warns that we will be overcome by an externally imposed oppression. But in Huxley's vision, no Big Brother is required to deprive people of their autonomy, maturity and history. As he saw it, people will come to love their oppression, to adore the technologies that undo their capacities to think. What Orwell feared were those who would ban books. What Huxley feared was that there would be no reason to ban a book, for there would be no one who wanted to read one. Orwell feared those who would deprive us of information. Huxley feared those who would give us so much that we would be reduced to passivity and egoism. Orwell feared that the truth would be concealed from us. Huxley feared the truth would be drowned in a sea of irrelevance. Orwell feared we would become a captive culture. Huxley feared we would become a trivial culture, preoccupied with some equivalent of the feelies, the orgy porgy, and the centrifugal bumblepuppy. As Huxley remarked in Brave New World Revisited, the civil libertarians and rationalists who are ever on the alert to oppose tyranny "failed to take into account man's almost infinite appetite for distractions". In 1984, Huxley added, people are controlled by inflicting pain. In Brave New World, they are controlled by inflicting pleasure. In short, Orwell feared that what we hate will ruin us. Huxley feared that what we love will ruin us. This book is about the possibility that Huxley, not Orwell, was right.”
 Seneca, Epistles to Lucillius, II, Loeb, tr Gummere
 Schopenhauer, A., ON THINKING FOR ONESELF, in THE ESSAYS OF ARTHUR SCHOPENHAUER Tr T. BAILEY SAUNDERS, THE ART OF LITERATURE Volume Six, Penn State Electronic Classics Series
 Bloom Harold, The Western Canon, The Books and School of the Ages, Harcourt Brace, new York.., 1994 Harold Bloom's WESTERN CANON is outlined conveniently at THE BOOKLIST CENTER
 Calvino, Italo, Why Read The Classics?, Vintage Books, New York, 2001
There are many other credible sources:
The editors of The Norwegian Book Clubs asked 100 prominent authors to nominate ten books that, in their opinion, are the ten best and most central works in world literature: THE 100 BEST BOOKS IN THE HISTORY OF LITERATURE
Borges, Jorge Luis; Eliot Weinberger (ed.,tr.); Esther Allen (tr.); Suzanne Jill Levine (tr.); Selected Non-fictions Penguin, 2000