Dang dude, that's deep. Theories on the human condition, existence, and life that I have enjoyed reading.

The World As I See It
An essay by Albert Einstein

"How strange is the lot of us mortals! Each of us is here for a brief sojourn; for what purpose he knows not, though he sometimes thinks he senses it. But without deeper reflection one knows from daily life that one exists for other people -- first of all for those upon whose smiles and well-being our own happiness is wholly dependent, and then for the many, unknown to us, to whose destinies we are bound by the ties of sympathy. A hundred times every day I remind myself that my inner and outer life are based on the labors of other men, living and dead, and that I must exert myself in order to give in the same measure as I have received and am still receiving...
"I have never looked upon ease and happiness as ends in themselves -- this critical basis I call the ideal of a pigsty. The ideals that have lighted my way, and time after time have given me new courage to face life cheerfully, have been Kindness, Beauty, and Truth. Without the sense of kinship with men of like mind, without the occupation with the objective world, the eternally unattainable in the field of art and scientific endeavors, life would have seemed empty to me. The trite objects of human efforts -- possessions, outward success, luxury -- have always seemed to me contemptible.
"My passionate sense of social justice and social responsibility has always contrasted oddly with my pronounced lack of need for direct contact with other human beings and human communities. I am truly a 'lone traveler' and have never belonged to my country, my home, my friends, or even my immediate family, with my whole heart; in the face of all these ties, I have never lost a sense of distance and a need for solitude..."
"My political ideal is democracy. Let every man be respected as an individual and no man idolized. It is an irony of fate that I myself have been the recipient of excessive admiration and reverence from my fellow-beings, through no fault, and no merit, of my own. The cause of this may well be the desire, unattainable for many, to understand the few ideas to which I have with my feeble powers attained through ceaseless struggle. I am quite aware that for any organization to reach its goals, one man must do the thinking and directing and generally bear the responsibility. But the led must not be coerced, they must be able to choose their leader. In my opinion, an autocratic system of coercion soon degenerates; force attracts men of low morality... The really valuable thing in the pageant of human life seems to me not the political state, but the creative, sentient individual, the personality; it alone creates the noble and the sublime, while the herd as such remains dull in thought and dull in feeling. "This topic brings me to that worst outcrop of herd life, the military system, which I abhor... This plague-spot of civilization ought to be abolished with all possible speed. Heroism on command, senseless violence, and all the loathsome nonsense that goes by the name of patriotism -- how passionately I hate them!
"The most beautiful experience we can have is the mysterious. It is the fundamental emotion that stands at the cradle of true art and true science. Whoever does not know it and can no longer wonder, no longer marvel, is as good as dead, and his eyes are dimmed. It was the experience of mystery -- even if mixed with fear -- that engendered religion. A knowledge of the existence of something we cannot penetrate, our perceptions of the profoundest reason and the most radiant beauty, which only in their most primitive forms are accessible to our minds: it is this knowledge and this emotion that constitute true religiosity. In this sense, and only this sense, I am a deeply religious man... I am satisfied with the mystery of life's eternity and with a knowledge, a sense, of the marvelous structure of existence -- as well as the humble attempt to understand even a tiny portion of the Reason that manifests itself in nature."




 www.aip.org/history/einstein/essay.htm

Heart of Darkness
Joseph Conrad

"In some inland post feel the savagery, the utter savagery, had closed round him--all that mysterious life of the wilderness that stirs in the forest, in the jungles, in the hearts of wild men. There's no initiation either into such mysteries. He has to live in the midst of the incomprehensible, which is detestable. And it has a fascination, too, which goes to work upon him. The fascination of the abomination--you know. Imagine the growing regrets, the longing to escape, the powerless disgust, the surrender, the hate."

"it is impossible to convey the life-sensation of any given epoch of one's existence--that which makes its truth, its meaning--its subtle and penetrating essence. It is impossible. We live, as we dream--alone."

Hamlet Act I. Scene III
(Lord Polonius to Laertes)

And these few precepts in thy memory
See thou character. Give thy thoughts no tongue,
Nor any unproportioned thought his act.
Be thou familiar, but by no means vulgar.
Those friends thou hast, and their adoption tried,
Grapple them to thy soul with hoops of steel;
But do not dull thy palm with entertainment
Of each new-hatch'd, unfledged comrade. Beware
Of entrance to a quarrel, but being in,
Bear't that the opposed may beware of thee.
Give every man thy ear, but few thy voice;
Take each man's censure, but reserve thy judgment.
Costly thy habit as thy purse can buy,
But not express'd in fancy; rich, not gaudy;
For the apparel oft proclaims the man,
And they in France of the best rank and station
Are of a most select and generous chief in that.
Neither a borrower nor a lender be;
For loan oft loses both itself and friend,
And borrowing dulls the edge of husbandry.
This above all: to thine ownself be true,
And it must follow, as the night the day,
Thou canst not then be false to any man.
Farewell: my blessing season this in thee!

For Whom The Bell Tolls 

(No Man is an Island) John Donne

No man is an island,
Entire of itself.
Each is a piece of the continent,
A part of the main.
If a clod be washed away by the sea,
Europe is the less.
As well as if a promontory were.
As well as if a manor of thine own
Or of thine friend's were.
Each man's death diminishes me,
For I am involved in mankind.
Therefore, send not to know
For whom the bell tolls,
It tolls for thee.

The famous poem was not originally crafted in modern English (obviously). Here is the original:

John Donne
Meditation 17
Devotions upon Emergent Occasions

"No man is an iland, intire of it selfe; every man is a peece of the Continent, a part of the maine; if a clod bee washed away by the Sea, Europe is the lesse, as well as if a Promontorie were, as well as if a Mannor of thy friends or of thine owne were; any mans death diminishes me, because I am involved in Mankinde; And therefore never send to know for whom the bell tolls; It tolls for thee...." 

Donne has such an opposing idea of existence from Conrad, yet both are easily applicable to life. We are all apart of one whole which will change if one element is lacking. When we die however, the world will continue turning and unless one is Marcus Tullius Ciscero or Winston Churchill, one's existence will be forgotten relatively quickly in the grand scheme of things being and to come. Moving on. 

HAMLET   V.I
(Hamlet to Horatio)

Not a whit, we defy augury: there's a special
providence in the fall of a sparrow. If it be now,
'tis not to come; if it be not to come, it will be
now; if it be not now, yet it will come: the
readiness is all: since no man has aught of what he
leaves, what is't to leave betimes? Let be.

A Satyre against Reason and Mankind

Based to some extent on Boileau's eighth satire,
this famous poem is also indebted to Hobbes, Montaigne,
and the tradition of le libertinage generally.

brkWere I (who to my cost already am One of those strange, prodigious creatures, man) A spirit free to choose, for my own share, What case of flesh and blood I pleased to wear, I'd be a dog, a monkey or a bear,	5
Or anything but that vain animal Who is so proud of being rational. brkThe senses are to gross, and he'll contrive A sixth, to contradict the other five, And before certain instinct, will prefer	10
Reason, which fifty times for one does err; Reason, an ignis fatuus in the mind, Which, leaving light of nature, sense, behind, Pathless and dangerous wandering ways it takes Through error's fenny bogs and thorny brakes;	15
Whilst the misguided follower climbs with pain Mountains of whimseys, heaped in his own brain; Stumbling from thought to thought, falls headlong down Into doubt's boundless sea, where, like to drown, Books bear him up a while, and make him try	20
To swim with bladders of philosophy; In hopes still to o'ertake th' escaping light, The vapor dances in his dazzling sight Till, spent, it leaves him to eternal night. Then old age and experience, hand in hand,	25
Lead him to death, and make him understand, After a search so painful and so long, That all his life he has been in the wrong. Huddled in dirt the reasoning engine lies, Who was proud, so witty, and so wise.	30
brkPride dew him in, as cheats their bubbles catch, And made him veneture to be made a wretch. His wisdom did his happiness destroy, Aiming to know that world he should enjoy. And wit was his vain, frivolous pretense	35
Of pleasing others at his own expense, For wits are treated just like common whores: First they're enjoyed, and then kicked out of doors. The pleasure past, a threatening doubt remains That frights th' enjoyer with succeeding pains.	40
Women and men of wit are dangerous tools, And ever fatal to admiring fools: Pleasure allures, and when the fops escape, 'Tis not that they're belov'd, but fortunate, And therefore, hat they fear at heart, they hate.	45
brkBut now, methinks, some formal band and beard Takes me to task. Come on, sir; I'm prepared. brk"Then, by your favor, anything that's writ Against this gibing, jingling knack called wit Light me abundantly; but you take care	50
Upon this point, not to be too severe. Perhaps my muse were fitter for this part, For I profess I can be very smart On wit, which I abhor with all my heart. I long to lash it in some sharp essay,	55
But your grand indiscretion bids me stay And turns my tide of ink another way. brk"What rage ferments in your degenerate mind To make you rail at reason and mankind? Blest, glorious man! to whom alone kind heaven	60
An everlasting soul has freely given, Whom his great Maker took such care to make That from himself he did the image take And this fair frame in shining reason dressed To dignify his nature above beast;	65
Reason, by whose aspiring influence We take a flight beyond material sense Dive into mysteries, then soaring pierce The flaming limits of the universe, Search heaven and hell, find out what's acted there,	70
And give the world true grounds of hope and fear." brkHold, mighty man, I cry, all this we know From the pathetic pen of Ingelo, From Patrick's Pilgrim, Sibbes' soliloquies, And 'tis this very reason I despise:	75
This supernatural gift, that makes a mite Think he's the image of the infinite, Comparing his short life, void of all rest, To the eternal and the ever blest; This busy, puzzling stirrer-up of doubt	80
That frames deep mysteries, then finds 'em out, Filling with frantic crowds of tinking fools Those reverend bedlams, colleges and schools; Borne on whose wings, each heavy sot can pierce The limits of the boundless universe;	85
So charming ointments make an old witch fly And bear a crippled carcass through the sky. 'Tis this exalted power, whose business lies In nonsense and impossibilities, This made a whimical philosopher	90
Before the spacious world, his tub prefer, And we have modern cloisterd coxcombs who Retire to think, 'cause they have nought to do. brkBut thoughts are given for action's government; Where action ceases, thought's impertinent.	95
Our sphere of action is life's happiness, And he who thinks beyond, thinks like an ass. Thus, whilst against false reasoning I inveigh, I own right reason, which I would obey: That reason which distinguishes by sense	100
And gives us rules of good and ill from thence, That bounds desires with a reforming will To keep 'em more in vigor, not to kill. Your reason hinders, mine helps to enjoy, Renewing appetites yours would destroy.	105
My reason is my friend, yours is a cheat; Hunger calls out, my reason bids me eat; Perversely, yours your appetite does mock: This asks for food, that answers, "What's o'clock?"" This plain distinction, sir, your doubt secures:	110
'Tis not true reason I despise, but yours. brkThus I think reason righted, bur for man, I'll ne'er recant; defend him if you can. For all his pride and his philosophy, 'Tis evident beasts are, in their degree,	115
As wise at least, and better far than he. Those creatures are the wisest who attain, By surest means, the ends at which they aim. If therefore Jowler finds and kills his hares Better than Meres supplies committee chairs,	120
Though one's a statesman, th' other but a hound, Jowler, in justice, would be wiser found. brkYou see how far man's wisdom here extends; Look next if human nature makes amends: Whose principles most generous are, and just,	125
And to whose morals you would sooner trust. Be judge yourself, I'll bring it to the test: Which is the basest creature, man or beast? Birds feed on birds, beasts on each other prey, But savage man alone does man betray.	130
Pressed by necessity, they kill for food; Man undoes man to do himself no good. With teeth and claws by nature armed, they hunt Nature's allowance, to supply their want. But man, with smiles, embraces, frendship, praise,	135
Inhumanly his fellow's life betrays; With voluntary pains works his distress, Not through necessity, but wantonness. brkFor hunger or for love they fight or tear, Whilst wretched man is still in arms for fear.	140
For fear he arms, and is of arms afraid, By fear to fear successively betrayed; Base fear, the source whence his best passions came: His boasted honor, and his dear-bought fame; That lust of power, to which he's a slave,	145
And for the which alone he dares be brave; To which his various projects are designed; Which makes him generous, affable, and kind; For which he takes such pains to be thought wise, And screws his actions in a forced disguise,	150
Leading a tedious life in misery Under laborious, mean hypocrisy. Look to the bottom of his vast design, Wherein man's wisdom, power, and glory join: The good he acts, the ill he does endure,	155
'Tis all from fear, to make himself secure. Merely for safety, after fame we thirst, For all me would be cowards if they durst. brkAnd honesty's against all common sense: Men must be knaves, 'tis in their own defence.	160
Mankind's dishonest, if you think it fair Amongst known cheats to play upon the square, You'll be undone. Nor can weak truth your reputation save: The knaves will all agree to call you knave.	165
Wronged shall he live, insulted o'er, oppressed, Who dares be less a villain than the rest. brkThus, sir, you see what human nature craves: Most men are cowards, all men should be knaves. The difference lies, as far as I can see,	170
Not in the thing itself, but the degree, And all the subject matter of debateIs only: Who's a knave of the first rate? brkAll this with indignation have I hurled At the pretending part of the proud world,	175
Who, swollen with selfish vanity, devise False freedoms, holy cheats, and formal lies Over their fellow slaves to tyrannize. brkBut if in Court so just a man there be (In Court a just man, yet unknown to me)	180
Who does his needful flattery direct, Not to oppress and ruin, but protect (Since flattery, which way soever laid, Is still a tax on that unhappy trade); If so upright a statesman you can find,	185
Whose passions bend to his unbiased mind, Who does his arts and policies apply To raise his country, not his family, Nor, whilst his pride owned avarice withstands, Receives close bribes through friends' corrupted hands -	190
brkIs there a churchman who on God relies; Whose life, his faith and doctrine justifies? Not one blown up with vain prelatic pride, Who, for reproof of sins, does man deride; Whose envious heart makes preaching a pretense,	195
With his obstreperous, saucy eloquence, To chide at kings, and rail at men of sense; None of that sensual tribe whose talents lie In avarice, pride, sloth, and gluttony; Who hunt good livings, but abhor good lives;	200
Whose lust exalted to that height arrives They act adultery with their own wives, And ere a score of years completed be, Can from the lofty pulput proudly see Half a large parish their own progeny;	205
Nor doting bishop who would be adored For domineering at the council board, A greater fop in business at fourscore, Fonder of serious toys, affected more, Than the gay, glittering fool at twenty proves	210
With all his noise, his tawdry clothes, and loves; brkBut a meek, humble man of honest sense, Who, preaching peace, does practice continence; Whose pious life's a proof he does believe Mysterious truths, which no man can conceive.	215
If upon the earth there dwell such GOd-like men, I'll here recant my paradox to them, Adore those shrines of virtue, homage pay, And, with the rabble world, their laws obey. brkIf such there be, yet grant me this at least:	220
Man differs more from man, than man from beast.

http://www.ealasaid.com/fan/rochester/satire.html