It occurs to me that garbage collection can be seen as some kind of dual of laziness. Laziness means deferring the creation of values until later in the future (or even never). Garbage collection means eagerly destroying data created in the past, and reclaiming the memory used by it, before some other event which would do so (in most garbage-collected languages, I think process destruction is the only other thing that frees memory, leaving aside foreign functions). If you don't have enough laziness (e.g. because of strict pattern matching on tuples) your program might do unnecesssary work (time wastage); if you don't have enough garbage collection (e.g. because a value will never be accessed again but is still referred to from something live), your program might leak memory (space wastage). Of course, space wastage can lead to time wastage, and vice-versa. Can this intuition be made any more formal? Is it merely of pedagogical use, or does anything interesting follow from it? -- Robin