A dictionary of Proverbs (Oxford Paperback Reference)

There are as good FISH in the sea as ever came out of it
Now often used as a consolation to rejected lovers: ‘there are plenty more fish in the sea’.

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  c 1573 G. HARVEY Letter-Book (1884) 126 In the mayne sea theres good stoare of fishe, And in delicate gardens.. Theres alwayes greate varietye of desirable flowers. 1816 T. L. PEACOCK Headlong Hall xiv. There never was a fish taken out of the sea, but left another as good behind. 1822 SCOTT Nigel III. x. Ye need not sigh sae deeply. .. There are as gude fish in the sea as ever came out of it. 1944 W. S. MAUGHAM Razor’s Edge iii. I’m a philosopher and I know there are as good fish in the sea as ever came out. I don’t blame her. You’re young. I’ve been young too. 2000 Washington Post 30 Nov. C11 (Garfield comic strip) ‘Yesiree, Garfield, there are lot of women out there. Yesiree. .. Plenty of fish in the sea. I’ll just cast out the old line.’ ‘Your bait’s dead.’ "love, blighted
  

All is FISH that comes to the net
Everything can be used to advantage. The is frequently replaced by a possessive pronoun or phrase. Similar in form and sense to all is GRIST that comes to the mill.

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  c 1520 in Ballads from MSS (1868-72) I. 95 Alle ys ffysshe that commyth to the nett. 1564 w. BULLEIN Dialogue against Fever 70 Takyng vp commoditie [opportunity], refusyng nothyng: all is fishe that commeth to the nette. 1680 BUNYAN Mr. Badman 19 What was his fathers could not escape his fingers, all was fish that came to his net. 1848 DICKENS Dombey & Son ix. ‘All’s fish that comes to your net, I suppose?’ ‘Certainly,’ said Mr. Brogley. ‘But sprats an’t whales, you know.’ 1936 A. CHRISTIE Murder in Mesopotamia xix. I don’t know that she cares for one more than the other. .. All’s fish that comes to her net at present. “gains and losses; opportunity
  

fish see also BETTER are small fish than an empty dish; BIG fish eat little fish; the CAT would eat fish, but would not wet her feet; when the LAST tree is cut down, the last fish eaten,.. you will realize that you cannot eat money; LITTLE fish are sweet; a WOMAN without a man is like a fish without a bicycle.