EigoPro 1級 読解 — The Mass We Cannot See

For nearly a century, astronomers have been confronted with an unsettling arithmetic: the luminous matter visible through our telescopes accounts for a mere fraction of the gravitational influence the cosmos demonstrably exerts. Galaxies rotate far too quickly to be held together by the stars and gas we can detect; clusters of galaxies move in ways that should fling them apart unless some unseen reservoir of mass binds them. From these discrepancies emerged the postulate of dark matter—a substance that neither emits, absorbs, nor reflects light, and is therefore wholly invisible to instruments designed to register radiation. What makes dark matter philosophically provocative is not merely that we cannot see it, but that its entire empirical warrant rests on inference. We do not observe the thing itself; we observe the gravitational shadows it casts and reason backward to its presence. This is hardly unprecedented in science—Neptune was deduced from perturbations in Uranus's orbit before anyone glimpsed it. Yet dark matter has stubbornly resisted every attempt at direct detection, and its persistent elusiveness has prompted some to wonder whether the inference itself might be flawed, whether our theory of gravity, rather than some exotic particle, is what requires revision. This predicament illuminates a deeper truth about observation. Science is often imagined as the disciplined accumulation of what can be seen, yet its most consequential claims frequently concern what cannot. The invisible is not the antithesis of evidence but, when rigorously inferred, a legitimate object of it. Dark matter thus stands as a reminder that the boundary between the observed and the merely deduced is more porous than naive empiricism allows, and that the universe's most abundant constituent may forever announce itself only through the company it keeps.

5問合格 60%以上普通

新規登録 または ログイン が必要です

この単元の問題を3問、解説つきで公開しています

1級 · 読解 · 全5問

問 1

Which statement best captures the central argument of the passage?

  • Astronomers prefer inference over direct observation because telescopes are inherently unreliable instruments for studying the cosmos.
  • Dark matter, though invisible, is a legitimate scientific object because its existence is rigorously inferred from gravitational effects, illustrating that science routinely relies on what cannot be directly observed.
  • The failure to detect dark matter directly demonstrates that the entire postulate is mistaken and that our theory of gravity needs no revision.
  • Dark matter has been conclusively detected through its gravitational shadows, proving that invisible substances can be observed as readily as luminous ones.
Phrase

the boundary between the observed and the merely deduced is more porous than naive empiricism allows

1級読解主旨把握論旨
⚡ひとことで

暗黒物質は推論によって正当化される科学的対象であり、観測されえないものに科学が依拠する事実を示す。

選択肢の解説Choice Analysis

「Dark matter, though invisible, is a legitimate scientific object because its existence is rigorously inferred from gravitational effects, illustrating that science routinely relies on what cannot be directly observed.」

正解

本文は、暗黒物質が直接観測されないにもかかわらず、重力効果からの厳密な推論によって科学的対象として認められる点を中心に論じている。最終段の「The invisible is not the antithesis of evidence but, when rigorously inferred, a legitimate object of it」がこの主張を端的に表す。観測と推論の境界が曖昧であるという認識論的洞察が結論である。

  • 「Dark matter has now been conclusively detected through its gravitational shadows, proving that invisible substances can be observed just as readily and as directly as ordinary luminous ones.」

    = 重力の影で暗黒物質が決定的に検出された ━ 本文は暗黒物質が「stubbornly resisted every attempt at direct detection」と述べ、決定的検出を明確に否定しているため誤り。。

  • 「The failure to detect dark matter directly demonstrates that the entire postulate is mistaken and that our theory of gravity needs no revision.」

    = 検出失敗は仮説そのものの誤りを証明する ━ 本文は検出失敗が仮説の見直しを「促す」可能性に言及するのみで、仮説が誤りだと断定していないため誤り。。

  • 「Astronomers prefer inference over direct observation because telescopes are inherently unreliable instruments for studying the cosmos.」

    = 望遠鏡が信頼できないため推論が好まれる ━ 本文は望遠鏡の信頼性を問題にしておらず、観測できないものへの推論の正当性を論じているため誤り。。

▦Collocation
パターン意味例
rest on inference推論に依拠するThe claim ultimately rests on inference rather than direct sight.
account for a fractionわずかな割合を占めるVisible matter accounts for only a small fraction of the total mass.
reason backward to〜へさかのぼって推論するScientists reason backward to a cause from its observed effects.
resist detection検出を拒むThe particle has resisted detection for decades.
cast a shadow影を落とすUnseen mass casts a gravitational shadow on passing light.
❝例文

  • The theory rests entirely on inference from indirect evidence.

    その理論はもっぱら間接的証拠からの推論に依拠している。

  • We reason backward from the symptoms to the disease.

    私たちは症状からさかのぼって病気を推論する。

  • Visible stars account for only a fraction of a galaxy's mass.

    見える星々は銀河の質量のわずかな部分しか占めない。

  • The suspect's motive remained invisible yet was rigorously inferred.

    容疑者の動機は見えなかったが厳密に推論された。

💡Tip · 覚えるコツ

主旨設問では、本文が「断定」したのか「示唆・問いかけ」にとどめたのかを見極める。decisively/conclusively などの強い語を含む選択肢は、本文が留保している場合に誤答になりやすい。

問 2

According to the passage, what observation first revealed a discrepancy involving unseen mass?

  • Neptune was observed to deviate from the orbit predicted by Newtonian mechanics.
  • Clusters of galaxies were seen to collapse inward under excessive visible mass.
  • Galaxies rotate far more rapidly than the gravity of their detectable stars and gas could sustain.
  • Telescopes recorded faint radiation emitted directly by dark matter particles.
Phrase

Galaxies rotate far too quickly to be held together by the stars and gas we can detect

1級読解詳細把握
⚡ひとことで

銀河が検出可能な質量だけでは説明できない速さで回転していることが矛盾を示した。

選択肢の解説Choice Analysis

「Galaxies rotate far more rapidly than the gravity of their detectable stars and gas could sustain.」

正解

第1段で「Galaxies rotate far too quickly to be held together by the stars and gas we can detect」と明記され、見える物質だけでは銀河をまとめられないことが矛盾の出発点とされる。これが暗黒物質の仮説を生んだ観測上の手がかりである。

  • 「Telescopes recorded faint radiation emitted directly by dark matter particles.」

    = 望遠鏡が暗黒物質の放射を記録した ━ 本文は暗黒物質が「neither emits, absorbs, nor reflects light」と述べており、放射の記録は不可能なため誤り。。

  • 「Neptune was observed to deviate sharply from the orbit predicted by Newtonian mechanics.」

    = 海王星がニュートン軌道から逸脱した ━ 海王星は推論の先例として挙げられるが、暗黒物質の矛盾を示した観測ではないため誤り。。

  • 「Clusters of galaxies were seen to collapse inward under excessive visible mass.」

    = 銀河団が過剰な可視質量で内側へ崩壊した ━ 本文は銀河団が「fling them apart」つまり飛散しかねない動きをすると述べており、内向きの崩壊ではないため誤り。。

▦Collocation
パターン意味例
hold togetherひとつにまとめるGravity holds the galaxy together against rotation.
far too quicklyあまりに速くThe disk spins far too quickly for visible mass to explain.
fling apartばらばらに飛散させるWithout extra mass, the cluster would fling itself apart.
fail to account for説明しきれないVisible gas fails to account for the observed speed.
bind a cluster銀河団を束縛するUnseen mass appears to bind the cluster gravitationally.
❝例文

  • The bridge swayed far too quickly for the wind alone to explain.

    橋は風だけでは説明できないほど速く揺れた。

  • Strong cables hold the structure together under stress.

    強靭なケーブルが応力下で構造をまとめている。

  • Without a binding force, the crowd would fling apart.

    束縛する力がなければ群衆はばらばらに散る。

  • The data fail to account for the sudden surge.

    そのデータは突然の急増を説明しきれない。

💡Tip · 覚えるコツ

詳細設問では、本文の動詞の方向性に注意。fling apart(外へ飛散)と collapse inward(内へ崩壊)は逆向きであり、方向を入れ替えた選択肢は典型的なひっかけ。

問 3

How does the passage characterize the case of Neptune?

  • As evidence that inference in astronomy almost always turns out to be mistaken.
  • As an example of a theory of gravity that had to be discarded entirely.
  • As proof that dark matter, like Neptune, will soon be detected directly.
  • As a precedent in which an unseen body was deduced from gravitational perturbations before being directly observed.
Phrase

Neptune was deduced from perturbations in Uranus's orbit before anyone glimpsed it

1級読解詳細把握
⚡ひとことで

海王星は、直接観測される前に重力の擾乱から推論された先例として挙げられている。

選択肢の解説Choice Analysis

「As a precedent in which an unseen body was deduced from gravitational perturbations before being directly observed.」

正解

第2段で海王星は「deduced from perturbations in Uranus's orbit before anyone glimpsed it」と説明され、推論が科学で前例のないものではないことを示す事例として提示される。暗黒物質の推論的性格を相対化する役割を担う。

  • 「As proof that dark matter, like Neptune, will soon be detected directly.」

    = 暗黒物質もまもなく直接検出される証拠 ━ 本文は海王星を推論の先例として挙げるのみで、暗黒物質の早期検出を予言していないため誤り。。

  • 「As an example of a theory of gravity that had to be discarded entirely.」

    = 破棄された重力理論の例 ━ 海王星はニュートン理論内で推論された成功例であり、理論破棄の例ではないため誤り。。

  • 「As evidence that inference in astronomy nearly always turns out in the end to be entirely mistaken.」

    = 天文学の推論はたいてい誤りだという証拠 ━ 海王星はむしろ推論が正しかった事例であり、推論の不信を示す例ではないため誤り。。

▦Collocation
パターン意味例
deduce from〜から推論するThe planet was deduced from orbital anomalies.
perturbation in an orbit軌道の擾乱A perturbation in Uranus's orbit hinted at a hidden body.
before anyone glimpsed it誰かが目にする前にThe world was predicted before anyone glimpsed it.
set a precedent前例をつくるNeptune set a precedent for inferred discovery.
confirm an inference推論を裏づけるLater observation confirmed the inference.
❝例文

  • The missing planet was deduced from tiny orbital perturbations.

    失われた惑星はわずかな軌道の擾乱から推論された。

  • His resignation was deduced from the tone of the memo.

    彼の辞任はメモの口調から推論された。

  • The discovery set a precedent for later astronomers.

    その発見は後の天文学者の前例となった。

  • Direct observation later confirmed the bold inference.

    後の直接観測がその大胆な推論を裏づけた。

💡Tip · 覚えるコツ

例示の機能を問う設問では、その例が主張を「支持」するのか「反証」するのか役割を特定する。海王星は推論の正当性を補強する肯定例である点を押さえる。

残り2問は、解いて確かめられます

全5問すべてに、この形式の解説が付いています。 間違えた問題は記録され、あとから復習できます。

無料で登録して続きを解く

インストール不要・カード登録なし・いま全機能無料

この単元の講義を見る1級の単元一覧1級の用語集