- 1
To deduce something is to reach an idea by using the knowledge and facts you already have. You do not see the answer sitting there. You put the pieces together and say, “So this must be true.” Detective stories made the word famous: someone looks at a wet coat and deduces that it has been raining.
To deduce something要deduce某件事, is是 by using利用 the knowledge and facts you already have你已經有的知識和事實 reach an idea得出一個想法。 You do not see你看不到 the answer sitting there擺在那裡的答案。 You put the pieces together你把各種線索拼湊起來 and say然後說, "So this must be true."「所以這一定是真的。」 Detective stories made the word famous偵探故事讓這個詞出名了: someone looks at a wet coat有人看到一件濕外套 and deduces推斷出 that it has been raining剛剛下過雨。
In ordinary life it is close to “figure out,” though deduce sounds more careful and more educated. Friends more often say guess or work out.
In ordinary life在日常生活裡 it is close to靠近 "figure out,"「figure out」（弄懂、想通） though deduce sounds more careful and more educated不過deduce聽起來更謹慎、更有學問。 Friends朋友之間 more often say guess or work out更常說guess（猜）或work out（想出來）。
Though actually, in a logic or science class the word is tighter. There, to deduce is to start from a general rule and arrive at a particular conclusion. The classroom partner is induce — going the other way, from examples toward a general rule. Outside class, almost nobody keeps that line so clean. People say deduce for any conclusion.
Though actually不過其實, in a logic or science class在邏輯課或科學課裡 the word is tighter這個詞用得更嚴謹。 There, in那裡 to deduce is to start from a general rule deduce是從一個通則開始 and arrive at a particular conclusion推出一個特定的結論。 The classroom partner課堂上的對應詞 is induce是induce（歸納） — going the other way反過來, from examples toward a general rule從例子推向通則。 Outside class離開課堂, almost nobody keeps that line so clean幾乎沒有人會把這條界線分得這麼清楚。 People say他們會說 deduce deduce for any reasoned conclusion來指任何有推理過程的結論。
組成From Late Middle English, borrowed from Latin dēdūcere, “to lead or bring away; (figuratively) to derive, discover, deduce”: dē- (from, away) + dūcere (to lead). The picture is leading an idea out of the facts you have.
同家族的字
- deductionthe noun: the act of reasoning this way — though the same noun also means an amount taken off a total, which belongs more with deduct
- deducibleadjective: able to be deduced
- deductfrom the same Latin verb dēdūcere, but English split them: deduce is for thinking, deduct is for taking numbers off
- produceshares Latin dūcere, “to lead”
- reduceshares Latin dūcere, “to lead”
- conductshares Latin dūcere, “to lead”
原始詞典資料6 筆記錄
以下是外部詞典記錄的用法，原文照列，我們還沒有寫成教學內容。上面的說明才是我們自己寫的；有些用法可能上面已經講過了。
deduceverb/dɪˈdʒuːs/
- 1
To reach (a conclusion) by applying rules of logic or other forms of reasoning to given premises or known facts.
- [T]he puritan buyldeth directly vpon the proteſtants firſt groundes in religion, & deduceth therof clearly and by ordinary conſequence al his concluſions, which the proteſtant cannot deny by divinity, but only by pollicy & humane ordination, or by turning to catholique anſwers contrary to ther owne principles: […]
- [T]hoſe principles or firſt poſitions, have no diſcordance with that reaſon, which draweth downe and diduceth the inferiour poſitions.
- 2
To examine, explain, or record (something) in an orderly manner.
- Pye[d-mantle]. […] Sir, I haue drawne / A Pedigree for her Grace, though yet a Nouice / In that ſo noble ſtudy. […] I haue deduc'd her.— […]
- It ſeems there is ſome angry Star that hath hung over this Buſineſs of the Palatinate from the beginning of theſe German Wars to this very Day, which will too evidently appear, if one ſhould mark and deduce Matters from their firſt Riſe.
- 3
archaicTo obtain (something) from some source; to derive.
- O Goddeſs, ſay, ſhall I deduce my rhimes / From the dire nation in its early times, / Europa’s rape, Agenor’s ſtern decree, / And Cadmus ſearching round the ſpacious ſea?
- The Spring whence thou [Hugh Myddelton] deduced'st the ample stream, / The Poet's and Historian's theme, / Trenching thy mighty aqueduct a way, / 'Till as the humble plains, the aspiring hills obey.
- 4
archaicTo be derived or obtained from some source.
- [B]y the ſtatute 7 Ann. c. 21 […] it is enacted, that, after the death of the pretender, and his ſons, no attainder for treaſon ſhall extend to the diſinheriting any heir, nor the prejudice of any perſon, other than the offender himſelf: which proviſions have indeed carried the remedy farther, than was required by the hardſhip above complained of; which is only the future obſtruction of deſcents, where the pedigree happens to be deduced through the blood of an attainted anceſtor.
- 5
obsoleteTo take away (something); to deduct, to subtract (something).
- to deduce a part from the whole
- Pra[ctise]. […] Well, Sir, the Contract / Is with this Gentleman, ten thouſand pound. […] Int[erest]. And what I have furniſh'd him with all o' the by, / To appeare, or ſo: A matter of foure hundred, / To be deduc'd upo' the payment—.
- 6
obsoleteTo lead (something) forth.
- Richard of the Vies will that Penda, K[ing] of Mereland, firſt deduced a colony of Cambridge men hither and cals it Crekelade, as other Kirklade with variety of names: […]
資料來源：英文維基詞典 English Wiktionary（CC BY-SA 4.0）。 原文照列，未經改寫。