How do you say 黑箱作业 in English?
The term &quot;黑箱&quot; was a direct translation of a science term &quot;Black box&quot; from English

&quot;Black box is a device, system or object which can be viewed in terms of its inputs and outputs (or transfer characteristics), without any knowledge of its internal workings.
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Almost anything might be referred to as a black box: a transistor, an engine, an algorithm, the human brain, an institution or government.

黑箱作业 in English should be ”black-box operation(s)” . (you can see what goes in and what comes out, but you never how the system works). Presuming the English speaker knows what is a 'black box'