When your opinion differ from the otherā€™s, it is a chance to get new idea. Letā€™s take a concrete example for that.

Suppose, a customer says ā€œI want a time machineā€. Letā€™s say you thought ā€œthat is physically impossibleā€. This is a conflict of opinion.

It is certainly impossible to physically create ā€œa vehicle for time travel.ā€ But, does the customerā€™s ā€œtime machineā€ really mean ā€œa vehicle for time travelā€? When you think ā€œIt is impossibleā€, you implicitly put the hypothesis that ā€œcustomers are using the word in the same meaning as mineā€. This hypothesis has not been verified.

The customer had something he/she want to express. But he/she does not know the good words to express that. So, he/she chose the word ā€œtime machineā€ from words he knew, because he/she thought it was the closest to what he/she want to express. This ā€œtime machineā€ is a metaphor. This ā€œtime machineā€ is the customerā€™s personal private language just spoken (I wrote about it in (6.2.5.5) Public Words and Private Words.)

Since you do not know the meaning of the word ā€œtime machineā€ used by customers, you need to ask various questions to understand:

  • ā€œWhat kind of time machine is that ā€˜time machineā€™?ā€
  • ā€œWhat is it possible to do with that ā€˜time machineā€™?ā€
  • ā€œWhen do you need that ā€˜time machineā€™?ā€ These question are similar to the clean question described in (6.2.4.2) Clean Language and Symbolic Modeling.

As a result of asking the customer, you found that the customer unintentionally overwrote an important file, and wanted to return to the past to get back the file. What he needs is ā€œa way to get the file before overwriteā€. That is the ā€œtime machineā€ in his/her language.

On the other hand, in language of programmers, that is ā€œsoftware to take back up automatically and restore past files when necessaryā€. Since the customer did not know the concept of ā€œautomatic backupā€, he/she chose the ā€œTime Machineā€.

Apple offers software named Time Machine. This is precisely ā€œsoftware to take back up automatically and restore past files when necessaryā€. It is a good naming that is easily understandable to customers who do not know the concept of automatic backup.


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