Book referring to software where you provide facts and the conclusion you want to reach

Question

I'm not sure if this is sci-fi, might be more humour (my mind keeps connecting it to Hitchhiker's Guide, so maybe same author/style, but really not sure about that).

Anyway, the key part I'm trying to find is someone writes software where, you enter the facts and the problem you are trying to solve, and the software uses the facts to produce the logical solution. This initial version doesn't sell at all.

So they rewrite the software so that you give it the facts AND the conclusion you want to reach, and the software produces the arguments that gets you there (whether logical or not).

I think there was a crack about the army and navy using it, but different versions..?

This was probably not a key part of the story (maybe only a page or two in the entire book), but it's the part I remember and liked the most.

Update: I read this at least 10 years ago, but it probably wasn't new even then.

Answer 1

This is surely "Dirk Gently's Holistic Detective Agency" a novel (and later TV series) by Douglas Adams - which explains the connection to the HHGTTG in your mind.

The program was written by Gordon Way:

Gordon’s great insight was to design a program which allowed you to specify in advance what decision you wished it to reach, and only then to give it all the facts. The program’s task, which it was able to accomplish with consummate ease, was simply to construct a plausible series of logical-sounding steps to connect the premises with the conclusion.

‘And I have to say that it worked brilliantly. Gordon was able to buy himself a Porsche almost immediately despite being completely broke and a hopeless driver. Even his bank manager was unable to find fault with his reasoning. Even when Gordon wrote it off three weeks later.’

‘Heavens. And did the program sell very well?’

‘No. We never sold a single copy.’

‘You astonish me. It sounds like a real winner to me.’

‘It was,’ said Richard hesitantly. ‘The entire project was bought up, lock, stock and barrel, by the Pentagon. The deal put WayForward on a very sound financial foundation.

There was indeed a crack about different services using different versions. By analysing Pentagon policies, it was apparent that the US Navy was using version 2.00, while for unknown reasons the Air Force was using the beta version of 1.5.