Traditional Interactive Fiction theory sees a game as consisting of a sequence of what we could call punctuated equilibria. The player gets a bit of story, and then gets to a puzzle, which they have to solve before they'll get to see anything new. This is IF as a cross between a novel and a crossword. The idea of doing this is that, firstly, the player gets rewarded for putting the effort in to complete the puzzles by furthering the story and hence has a motive to keep going; secondly that the story's advancement is more appreciated by the player thanks to the anticipation that preceded it; thirdly that because the player spends a while looking carefully around the locations open to them, and playing with the objects available, they become further immersed in the environment the puzzle is set in (and hence in the story itself); and lastly because for the player to have to spend so long on what can actually be quite short (in terms of code) sequences makes the game appear much bigger than it is, and so the author has to put less work to get what seems to be a decent sized game. Thanks to all these factors, puzzles were an integral part of all the commercial works of interactive fiction (or rather, text adventure games), and of the early post-commercial games.

However, there has in recent years been a growing trend to reduce the emphasis on puzzles, or even to do away with them altogether. Puzzles, according to this new view of IF, get in the way of the story - and this is a bad thing. The story should flow as a continuous whole. And, importantly, interactivity need not come solely in the form of puzzle-solving. The important thing about interactivity, in this view, the crucial point, is that it provides a sense of immersion. What IF has to offer above static fiction is a heightened sense of actually being there, of a real identification with the protagonist - not just because you're following their story, or even because you're in their heads, but because you are them. This does not, importantly, require the player to be able to control the plot - though that is an interesting, and dangerous, road to go down - all that is required is small-scale, local interaction. The important point is that the player has to actively extract the information, rather than just be passively given it. As Marnie Parker puts it in her "Iffy Theory" ( -

Like an infant reaching out to pull a piece of the world, the "not me," in closer to explore it -- we pull data into our mental reach to process it, making it part of our consciousness and memory, making it "me." Boundaries between information processor and information system start to become lost the moment we tangibly reach outward. This physical act of "bringing it closer" is unequaled by watching or reading alone.

Of course, puzzleless IF has taken a number of forms, and I'm sure not all the authors concerned would agree with my summary of the theory. Of particular note are Adam Cadre's Photopia, which could be blamed for starting the puzzleless trend, and Jon Ingold's All Roads - which won the 2001 annual competition. These two exemplify the cut-up, filmic technique of having the story told in a sequence of short scenes - which has the advantage of making it easy to effectively and unobtrusively constrain interactivity to a manageable level. Also worth a look are the oddities A Space Under The Window (Andrew Plotkin) and Aisle (Sam Barlow) which both could be classed as puzzleless, and the entries to Marnie Parker's IF Art Show, which encourages works both puzzleless and plotless - see in particular Emily Short's Galatea. There are also a number of pieces which could be said to be on the edge of puzzleless, ones which do have puzzles but where they are definitely subservient to the story. In fact, this is to some extent now the norm, with pure puzzle games like Zork or Adventure increasingly rare, and puzzleless IF could be said to be merely the ultimate expression of that trend. Worlds Apart (Suzanne Britton, winner of XYZZY Award for Best Writing 1999) is a particularly good example of puzzles not being allowed to get in the way of the plot.