He who imagines he can do without the world, deceives himself much: but he who fancies the world cannot do without him, is under a far greater deception.
 
[Celui qui croit pouvoir trouver en soi-même de quoi se passer de tout le monde se trompe fort; mais celui qui croit qu’on ne peut se passer de lui se trompe encore davantage.]

François VI, duc de La Rochefoucauld (1613-1680) French epigrammatist, memoirist, noble

Réflexions ou sentences et maximes morales [Reflections; or Sentences and Moral Maxims], ¶201 (1665-1678) [ed. Carvill (1835), ¶81]
    (Source)

Appeared in the 1st ed. (1665). In manuscript, the first part "Celui qui croit pouvoir trouver en soi-même de quoi se passer de tout le monde" reads "Celui qui croit pouvoir se passer de tout le monde" ("He who believes that he can find in himself enough to do without everyone" reads "He who believes he can do without everyone.").

(Source (French)). Alternate translations:

He that fansies such a sufficiency in himself, that he can live without all the World, is mightily mistaken; but he that imagines himself so necessary, that other people cannot live without him, is a great deal more mistaken.
[tr. Stanhope (1694), ¶202]

He who imagines he can do without the world deceives himself much; but he who fancies the world cannot do without him is still more mistaken.
[pub. Donaldson (1783), ¶93; ed. Lepoittevin-Lacroix (1797), ¶192]

He who thinks he can find in himself the means of doing without others is much mistaken; but he who thinks that others cannot do without him is still more mistaken.
[ed. Gowens (1851), ¶210]

He who thinks he has the power to content the world greatly deceives himself, but he who thinks that the world cannot be content with him deceives himself yet more.
[tr. Bund/Friswell (1871), ¶201]

The man who thinks he can do without the world errs; but the man who thinks the world can [sic] do without him is in still greater error.
[tr. Heard (1917), ¶206]

It is a great mistake for a man to suppose that he can dispense with the world; but it is a much greater one to suppose that the world cannot dispense with him.
[tr. Stevens (1939), ¶201]

A man who believes that his inner resources are such that he can dispense with his fellow-men is committing a serious mistake: it is not, however, so serious as that of the man who believes himself indispensable to others.
[tr. FitzGibbon (1957), ¶201]

The man who thinks he can do without the world is indeed mistaken; but the man who thinks the world cannot do without him is mistaken even worse.
[tr. Kronenberger (1959), ¶201]

The man who thinks he can find enough in himself to be able to dispense with everybody else makes a great mistake, but the man who thinks he is indispensable to others makes an even greater.
[tr. Tancock (1959), ¶201]

He who believes that he can make do without any one else in the world, is very mistaken; but he who believes that nobody in the world could make do without him, deceives himself still more greatly.
[tr. Whichello (2016) ¶201]