# Arithmetic and relative clauses

Consider the following sentence:

Eight minus one is seven.

This doesn't seem to obey the usual grammar rules. If I think of 引く as a verb meaning 'to subtract' then I have a relative clause 八引く modifying 一, so 八引く一 ought to be 'one where we subtract eight' i.e. the grammatical answer should be -7 rather than +7.

I suppose I ought to be suspicious of this analysis since there is no を on 八. What is the correct way to think about this sentence? Should I abandon trying to think of 引く as 'to subtract' and just use a plain 'minus'?

What if I had added the を i.e. 八を引く一は七です. Would this be grammatical? Would it change the meaning?

• What is the context for this sentence? Was it written out like that? Typically I see that language used not as a standalone sentence, but as a vocalization of the formula " 8 - 1 = 7 ". Commented Apr 25, 2021 at 22:55
• This is how, as @SpiritTamer mentioned, a line of mathematics is read. It is not how it would otherwise be expressed. Commented Apr 26, 2021 at 0:50
• @A.Ellett You and the other commenter seem to have misssed the point of this interesting question: yes, of course that's how arithmetic is read; but how did this construction become to be considered idiomatic, in spite of its contradictory grammatical structure? (I suspect that adherence to left-to-right associativity of (western) math operator syntax was considered a more important consideration than Japanese clausal right-to-left associativity when the system was introduced in Japan (Meiji era?), but why the 連体形 istead of using the 連用形, for example「8引き1」?)
– Will
Commented Apr 26, 2021 at 1:00
• Commented Apr 26, 2021 at 8:45