jam tomorrow

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jam tomorrow

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From Lewis Carroll's Through the Looking-Glass (1871), where Alice is offered “jam to-morrow and jam yesterday — but never jam to-day”. This is a pun on a mnemonic for the usage of jam, iam in Latin (note i/j conflation in Latin spelling), which means “now”, but only in the future or past tense, not in the present (which is instead nunc).

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jam tomorrow (uncountable)

1. (idiomatic) Promised benefits that never arrive.
   • 1930, John Maynard Keynes, Economic Possibilities for Our Grandchildren:

     The “purposive” man ... does not love his cat, but his cat’s kittens; nor, in truth, the kittens, but only the kittens’ kittens, and so on forward forever to the end of cat-dom. For him jam is not jam unless it is a case of jam to-morrow and never jam to-day.

   • 1961 October, Bulletin of the Atomic Scientists, volume 17, number 8:

     Yet they've proved that common men can show astonishing fortitude in chasing jam tomorrow.

   • 1978, Eileen M. Byrne, Women and education:

     It always seems to be a problem to be dealt with when resources (later) permit. Jam tomorrow, as usual.

2. (idiomatic, economics, by extension) Availability of a resource at a future date.
   • 1974, Lawrence H. Officer, Lawrence Berk Smith, Issues in Canadian Economics, McGraw-Hill Ryerson, page 336:

     The consumption-possibilities curve illustrates the choice which must be made: more jam today means less jam tomorrow; less jam today means more jam tomorrow.

   • 1985, Phillip Crowson, Economics for Managers: A Professionals’ Guide, 3rd edition, Macmillan Press, page 26:

     A basic human characteristic is the preference for consumption today over consumption tomorrow. Jam today is always better than jam tomorrow, unless sufficient incentive is offered to forgo the immediate enjoyment of today's jam. This is not because of uncertainty about the likely receipt of tomorrow's jam, but merely a property of the passage of time.

   • 1985, Joel Mokyr, The Economics of the Industrial Revolution, Rowman & Littlefield Publishers, page 216:

     For one-period optimization, the obvious course of action to maximize consumption is to consume the whole of output by “eating up” the capital stock. The inapplicability of this tactic to an industrializing nation is transparent—it gets a lot of jam for today but leaves little for tomorrow. Jam today has therefore to be balanced against jam tomorrow.

• pie in the sky

• (economics): jam today

• Gary Martin (1997–) “Jam tomorrow”, in The Phrase Finder, retrieved 26 February 2017.