斯宾诺莎，从来就没有墙
Spinoza, There Was Never a Wall
一、磨镜片
海牙。一间小房间。一个人坐在磨镜片机前面。
他每天磨镜片。望远镜的，显微镜的。精密的手工活。玻璃粉飘在空气里。他吸进去。一点一点地，每天。
他叫巴鲁赫·斯宾诺莎。他二十三岁被犹太社区逐出教门。逐出令用的词是"可憎的异端"和"骇人的行为"。逐出令禁止任何犹太人跟他说话，禁止任何人靠近他六英尺以内。
他没有反抗。他没有申诉。他改了名字——从希伯来文的"巴鲁赫"改成拉丁文的"贝内迪克特"。两个名字的意思一样：被祝福的。
然后他磨镜片。白天磨。晚上写。他写了十五年。写了一本书。用几何学的方法写的——定义，公理，命题，证明。像欧几里得写几何原本一样写哲学。
1677年2月21日。他死了。四十四岁。肺病。玻璃粉。
他死后，朋友们出版了那本书。《伦理学》（Ethica Ordine Geometrico Demonstrata）。
这本书说了一件事：一切都是一个东西。
二、神即自然
Deus sive Natura。神即自然。
这三个拉丁词是斯宾诺莎哲学的心脏。
柏拉图说世界分两层：影子和理念。影子是你看到的，理念是真实的。中间有一条线。 康德说世界分两层：现象和物自体。现象是你感知到的，物自体是你够不到的。中间有一条线。 笛卡尔说世界分两种东西：心灵和物质。思维是一种，广延是另一种。中间有一条线。
斯宾诺莎说：没有两层。没有两种。只有一个东西。
那个东西就是实体（Substance）。实体不依赖任何别的东西存在。它是自因的——自己是自己的原因。它是无限的——因为没有任何东西在它外面限制它。
斯宾诺莎管它叫"神"。也管它叫"自然"。不是因为他想挑衅——是因为在他的系统里，这两个词指的是同一个东西。神不在自然外面。神就是自然。自然就是神。没有创造者和被造物的区分。没有超越的那个和被超越的这个。一切在一个里面。
你在里面。我在里面。这把椅子在里面。每一个思想在里面。每一块石头在里面。不是说它们是神的"部分"——是说它们是神的"样态"（modes），是唯一实体在不同属性下的不同表达。
思维和广延不是两种不同的东西。它们是同一个实体的两个属性。你的思想和你的身体不是两个东西——是同一个东西的两面。跟波和粒子不是两个东西是同一个东西的两面一样。
等一下。这不就是玻尔的互补性吗？
三、他和这一轮
第三轮从柏拉图开始。柏拉图说：构可以闭合。理念是真实的。影子背后有太阳。你可以走出洞穴。
然后第三轮花了十六篇凿这堵墙。
休谟从下面凿——地基是沙子，但沙子够用。 叔本华从里面凿——底下有意志，盲目的，永不满足的。 克尔凯郭尔从外面凿——体系里没有"我"。 图灵用数学凿——停机问题，构不可闭合。 康托尔用数学凿——连续统假设，永远不可判定。 哥白尼凿了假位置——地球不在中心。 蒯因凿了假工具——分析/综合之间没有那条线。 海森堡凿了假分界——观察者和被观察者之间没有那条线。 波伏瓦凿了假本质——"女人"不是天生的。 玻尔说两面都对——互补性。
十六种凿法。十六个人。凿的都是同一堵墙：你以为世界可以被一条线分成两半。不可以。
斯宾诺莎收尾。他不凿墙。他说：从来就没有墙。
不是"墙被凿开了"。是"墙不存在"。你以为有两个东西——神和自然，心灵和物质，主体和客体，影子和理念。从来就是一个东西。你画了一条线在中间。线是你画的。东西是一个。
蒯因说"没有那条线"——他是从认识论说的。 海森堡说"测不准"——他是从物理学说的。 西田说"主客未分"——他是从存在论说的。 斯宾诺莎说"神即自然"——他是从形而上学说的。
四个人。四个层面。同一件事。
但斯宾诺莎比其他三个更彻底。蒯因只是说你画不出那条线。海森堡说你测不准。西田说线是后来画的。斯宾诺莎说从来只有一个东西——你为什么要画线？
四、几何学的安静
《伦理学》是用几何学的方法写的。
定义。公理。命题。证明。附释。
没有故事。没有比喻。没有激情。没有愤怒。没有眼泪。
蒯因的凿是最干净的。斯宾诺莎的构是最安静的。
一个命题接着一个命题。每一个都从前一个推出来。你不同意可以。但你得指出哪一步推理出了问题。不是"我不喜欢你的结论"——是"你的第几步推理有逻辑错误"。
这是一种极端的方法。把哲学变成数学。把关于神和人和自由和幸福的问题用定理来回答。
为什么？
因为斯宾诺莎不相信激情能通向真理。他相信理性。不是抽象的、冷的理性——是一种安静的、清晰的、不受情绪干扰的看。当你用这种方式看世界，你看到的是必然性。一切都是必然的。不是因为有一个神在安排——是因为一切都从实体的本性必然地流出来。
自由不是没有必然性。自由是理解必然性。你理解了为什么一切必然是这样的，你就不再被激情驱使了。你不是克制激情——你是超越了激情。
这跟托尔斯泰完全相反。托尔斯泰说你应该用意志克制欲望（药方）。斯宾诺莎说你应该用理解消解欲望（几何学）。
托尔斯泰开药方。斯宾诺莎不开药方。他画图纸。你自己看。看懂了你就自由了。看不懂也没关系——你只是还在里面。
五、他和康德
斯宾诺莎跟康德的关系需要在这里说。
康德说物自体不可知。帘子后面有东西，但你永远看不到。你只能看到帘子这边——现象。
斯宾诺莎说没有帘子。一切都是一个东西的不同表达。你在里面。物自体不在"帘子后面"——它就是你所在的一切。你不是在"看"世界——你是世界的一部分在"看"自己。
康德划了一条线：现象/物自体。 斯宾诺莎说从来就没有那条线。
SAE的位置在两者之间。SAE同意康德的"不可闭合"——你的构永远有余项。但SAE不同意康德的"不可知"。SAE说可以逼近。一层一层地逼近。凿一层，看到一层。再凿，再看到。永远到不了底——但可以一直走。
SAE没有凿康德。SAE凿的是"不可知"这三个字，改成了"不可闭合但可逼近"。
斯宾诺莎更激进。他不说"逼近"。他说"你已经在那里了"。你不需要逼近物自体——你就是物自体的一个样态。你不需要走过帘子——帘子不存在。
这是最安静的立场。也是最难活的立场。因为如果一切都是一个东西，如果一切都是必然的，如果自由只是理解必然性——那你的痛苦，你的遗憾，你的余项，全都是必然的。不是你做错了什么。是一切都不可能不是这样。
你要跟这个活在一起。
六、他和居里夫人
一个不太明显的对比。
居里夫人被自己的发现杀死了——镭的辐射。 斯宾诺莎被自己的职业杀死了——镜片的玻璃粉。
两个人都被自己用来谋生的东西慢慢杀死了。居里夫人用镭做研究。斯宾诺莎磨镜片维持生活。两个人的身体一点一点被侵蚀。两个人都知道（或者应该知道）自己在做的事情有风险。两个人都没有停。
居里夫人没有停是因为发现太重要了。 斯宾诺莎没有停是因为他需要独立。他拒绝了海德堡大学的教授职位。他不想依附于任何机构。磨镜片让他自由——自由地想，自由地写，不欠任何人。
自由的代价是玻璃粉。
七、收尾
这是第三轮的最后一篇。
第三轮从柏拉图开始——"那天他不在"。柏拉图在苏格拉底喝毒酒那天不在场。他从那个缺席里长出了一整套哲学——理念论。他需要一个苏格拉底死不了的世界。他建了墙。
第三轮用斯宾诺莎结束——"从来就没有墙"。
十八篇。十八个人。从"构可以闭合"到"从来就没有墙"。
中间经过了什么？
休谟说沙子够用。叔本华说底下有兽。克尔凯郭尔跳了。图灵咬了苹果。契诃夫什么也没说。康托尔看到了无穷。哥白尼放下书走了。蒯因说没有那条线。波伏瓦举着镜子。特斯拉听到了嗡嗡声。爱迪生灯亮了一秒然后灭了。海森堡测不准。玻尔说对面也是。托尔斯泰递出了一张吃不下去的药方。莎士比亚不在。
然后斯宾诺莎来了。他说了一句话。最安静的一句话。也是最大的一句话。
从来就没有墙。
八、磨镜片（续）
他磨了一辈子镜片。
镜片是干什么的？让你看到本来看不到的东西。望远镜让你看到远处的星星。显微镜让你看到近处的细胞。
他磨镜片。他也写《伦理学》。两件事其实是一件事。镜片让你看到物理上看不到的东西。《伦理学》让你看到概念上看不到的东西——那个唯一的实体，那个一切都在其中的东西，那个从来就没有墙的世界。
他磨镜片磨死了自己。他写《伦理学》写活了一个世界。
九、一个东西
1677年2月21日。海牙。
斯宾诺莎去世。四十四岁。
他死后朋友们出版了《伦理学》。书出来之后立刻被禁了。被当成无神论。被当成危险的东西。
两百年后它复活了。黑格尔说斯宾诺莎是"所有现代哲学的起点"。歌德被他迷住了。诺瓦利斯叫他"陶醉于神的人"。爱因斯坦被问到他信不信上帝的时候说："我信斯宾诺莎的上帝。"
他的书活了。他不在了。跟莎士比亚一样。
桥头上又多了一个人。最后一个。
他站在最安静的位置。哪个位置？说不清。不是因为测不准（海森堡），是因为他在哪里不重要——在他的世界里，所有位置都是同一个东西的不同样态。他站在这里和站在那里没有区别。
他手里什么也没拿。没有苹果（图灵），没有灯泡（爱迪生），没有药方（托尔斯泰），没有信（玻尔），没有公式（海森堡），没有镜子（波伏瓦），没有书（哥白尼）。
他的手里有一点玻璃粉。磨镜片留下的。
苏格拉底站在空地上。柏拉图蹲着画图纸。休谟打台球。叔本华看桥底下。克尔凯郭尔跳了。图灵看手里的苹果。契诃夫靠着栏杆。康托尔看天上。哥白尼放下书走了。萨特转来转去。波伏瓦举着镜子。蒯因说了一句"没有那条线"。特斯拉听嗡嗡声。爱迪生拿着灯泡。海森堡位置不确定。玻尔拿着没寄出的信。托尔斯泰拿着药方。莎士比亚不在——他是桥下面的水。
斯宾诺莎看着他们所有人。
他看到了什么？
他看到了一个东西。不是很多人站在一座桥上。是一个东西。桥是它。水是它。人是它。苹果是它。灯泡是它。药方是它。镜子是它。公式是它。沉默是它。嗡嗡声是它。等待是它。离开也是它。
一个东西。
他弯下腰。他把手上的玻璃粉吹散了。粉尘落在桥面上。落在所有人身上。很细。几乎看不见。
Deus sive Natura。
然后他站直了。他什么也没说。
第三轮结束了。[1][2]
注释
[1]: 斯宾诺莎"从来就没有墙"与Self-as-an-End理论中"凿构循环"和"构不可闭合"的关系：凿构循环的核心论证见系列方法论总论（DOI: 10.5281/zenodo.18842450）。斯宾诺莎是第三轮的收尾：柏拉图开篇（"构可以闭合"），十六篇从不同方向凿墙，斯宾诺莎收尾（"从来就没有墙"）。他的"Deus sive Natura"（神即自然）是最彻底的"没有那条线"——不是说线被凿掉了，是说从来只有一个东西。与蒯因-海森堡-西田-玻尔的多层平行：蒯因（认识论），海森堡（物理学），西田（存在论），玻尔（物理学解释），斯宾诺莎（形而上学）——五个层面同一件事。斯宾诺莎比其他四个更彻底：他不说"线画不出来"，他说"为什么要画线"。与康德/SAE的关系：康德说物自体不可知；SAE说不可闭合但可逼近；斯宾诺莎说你已经在那里了——帘子不存在。与托尔斯泰的对比：托尔斯泰用意志克制欲望（药方），斯宾诺莎用理解消解欲望（几何学）。磨镜片=用手工活维持独立（拒绝了海德堡教职），也被手工活杀死了——跟居里夫人被自己的发现杀死同一个结构。
[2]: 斯宾诺莎生平主要依据Steven Nadler, Spinoza: A Life (1999)及Roger Scruton, Spinoza: A Very Short Introduction (2002)。出生于阿姆斯特丹（1632年11月24日），葡萄牙裔犹太家庭（马拉诺人）。犹太社区逐出教门（1656年7月27日），逐出令措辞参考Amsterdam Municipal Archives。"巴鲁赫"改"贝内迪克特"参考Nadler。磨镜片职业参考多部传记。拒绝海德堡大学教职（1673年）参考Nadler。"Deus sive Natura"（神即自然）见《伦理学》第四部分前言，另参考Stanford Encyclopedia of Philosophy条目。《伦理学》（Ethica Ordine Geometrico Demonstrata）用几何学方法写成，1677年死后出版。Natura naturans / Natura naturata区分见《伦理学》第一部分。《神学政治论》（Tractatus Theologico-Politicus, 1670年）。黑格尔"所有现代哲学的起点"参考黑格尔《哲学史讲演录》。诺瓦利斯"陶醉于神的人"参考Novalis, Blütenstaub。爱因斯坦"我信斯宾诺莎的上帝"参考1929年致Rabbi Herbert S. Goldstein电报。斯宾诺莎去世（1677年2月21日，海牙），死因肺病，可能与磨镜片的玻璃粉有关。系列第三轮第十八篇（收官篇）。前五十八篇见nondubito.net。
I. Grinding Lenses
The Hague. A small room. A man sits at a lens-grinding machine.
He grinds lenses every day. For telescopes. For microscopes. Precision handwork. Glass dust hangs in the air. He breathes it in. A little each day.
His name is Baruch Spinoza. At twenty-three he was excommunicated from the Jewish community in Amsterdam. The decree used the words "abominable heresies" and "monstrous deeds." It forbade any Jew from speaking to him or coming within six feet of him.
He did not fight back. He did not appeal. He changed his name—from the Hebrew "Baruch" to the Latin "Benedictus." Both mean the same thing: blessed.
Then he ground lenses. During the day, he ground. At night, he wrote. He wrote for fifteen years. He produced one book. Written in the geometric method—definitions, axioms, propositions, proofs. Philosophy structured like Euclid's Elements.
February 21, 1677. He dies. Forty-four years old. Lung disease. Glass dust.
After his death, his friends publish the book. Ethics (Ethica Ordine Geometrico Demonstrata).
The book says one thing: everything is one thing.
II. God or Nature
Deus sive Natura. God or Nature.
These three Latin words are the heart of Spinoza's philosophy.
Plato says the world has two layers: shadows and Forms. The line between them is real. Descartes says the world has two kinds of stuff: mind and matter. The line between them is real. Kant says the world has two sides: phenomena and the thing-in-itself. The line between them is real.
Spinoza says: there are not two layers. There are not two kinds. There is one thing.
That thing is Substance. Substance depends on nothing else for its existence. It is self-caused. It is infinite—because nothing outside it limits it.
Spinoza calls it "God." He also calls it "Nature." Not to provoke—but because in his system, these two words refer to the same thing. God is not outside Nature. God is Nature. Nature is God. No distinction between creator and created. No transcendent being standing apart. Everything within one.
You are in it. I am in it. This chair is in it. Every thought is in it. Every stone. Not as "parts" of God—as modes of God, expressions of the single Substance under different attributes.
Thought and extension are not two different things. They are two attributes of the same Substance. Your mind and your body are not two things—they are two faces of one thing. Like wave and particle are not two things but two faces of one thing.
Wait. Isn't that Bohr's complementarity?
III. Spinoza and This Cycle
The third cycle begins with Plato. Plato says: constructs can be closed. The Forms are real. There is a sun outside the cave. You can climb out.
Then the third cycle spends sixteen essays chiseling that wall.
Hume from below—the foundation is sand, but sand suffices. Schopenhauer from inside—beneath lies blind will. Kierkegaard from outside—the system has no "I." Turing with mathematics—the halting problem, constructs cannot close. Cantor with mathematics—the continuum hypothesis, forever undecidable. Copernicus chisels false position—Earth is not at the center. Quine chisels the false tool—no line between analytic and synthetic. Heisenberg chisels the false boundary—observer and observed inseparable. Beauvoir chisels false essence—"woman" is not born but made. Bohr says both sides are correct—complementarity.
Sixteen ways. Sixteen people. All chiseling the same wall: you believe the world can be divided in two by a line. It cannot.
Spinoza closes the cycle. He does not chisel the wall. He says: there was never a wall.
Not "the wall has been broken." The wall does not exist. You thought there were two things—God and Nature, mind and matter, subject and object, shadow and Form. There was always one thing. You drew a line in the middle. The line is yours. The thing is one.
Quine says "there is no such line"—from epistemology. Heisenberg says "uncertain"—from physics. Nishida says "prior to subject-object"—from ontology. Spinoza says "God or Nature"—from metaphysics.
Four people. Four levels. The same insight.
But Spinoza is more thoroughgoing than the other three. Quine says you cannot draw the line. Heisenberg says you cannot measure across it. Nishida says the line was drawn afterward. Spinoza says there was only ever one thing—why would you draw a line?
IV. The Quiet of Geometry
The Ethics is written in the geometric method.
Definitions. Axioms. Propositions. Proofs. Scholia.
No stories. No metaphors. No passion. No anger. No tears.
Quine's chisel is the cleanest in the series. Spinoza's construct is the quietest.
One proposition follows from the last. Each derived from what precedes it. You may disagree. But you must point to the step where the reasoning fails. Not "I don't like your conclusion"—"your inference at step n is invalid."
This is an extreme method. Turning philosophy into mathematics. Answering questions about God, humanity, freedom, and happiness with theorems.
Why?
Because Spinoza does not believe passion leads to truth. He trusts reason. Not abstract, cold reason—a quiet, clear, undisturbed seeing. When you see the world this way, what you see is necessity. Everything is necessary. Not because a God arranges it—because everything flows necessarily from the nature of Substance.
Freedom is not the absence of necessity. Freedom is the understanding of necessity. Once you understand why everything is necessarily as it is, you are no longer driven by passion. You do not suppress passion—you transcend it.
This is the opposite of Tolstoy. Tolstoy says: use willpower to restrain desire (prescription). Spinoza says: use understanding to dissolve desire (geometry).
Tolstoy prescribes. Spinoza does not prescribe. He draws blueprints. You look for yourself. Understand, and you are free. Don't understand—you are simply still inside.
V. Spinoza and Kant
The continuation prompt notes: "SAE did not chisel Kant; it chiseled 'the unknowable' → replaced with 'cannot be closed but can be approached.'"
Spinoza's relation to Kant needs to be stated here.
Kant says the thing-in-itself is unknowable. Something lies behind the curtain, but you can never see it. You see only this side—phenomena.
Spinoza says there is no curtain. Everything is one thing expressed differently. You are inside it. The thing-in-itself is not "behind a curtain"—it is everything you inhabit. You are not "looking at" the world—you are a part of the world looking at itself.
Kant draws a line: phenomena / thing-in-itself. Spinoza says that line was never there.
SAE's position is between them. SAE agrees with Kant's "cannot be closed"—your construct always has remainder. But SAE disagrees with Kant's "unknowable." SAE says: approachable. Layer by layer. Chisel a layer, see a layer. Chisel again, see again. You never reach the bottom—but you can keep going.
Spinoza is more radical. He doesn't say "approach." He says: you are already there. You don't need to approach the thing-in-itself—you are a mode of it. You don't need to pass through the curtain—the curtain does not exist.
This is the quietest position. It is also the hardest to live. Because if everything is one thing, if everything is necessary, if freedom is only the understanding of necessity—then your pain, your regret, your remainder, are all necessary. Not because you did something wrong. Because everything could not have been otherwise.
You must live with this.
VI. Spinoza and Marie Curie
A less obvious comparison.
Curie is killed by her own discovery—radium's radiation. Spinoza is killed by his own trade—glass dust from lens grinding.
Both are slowly destroyed by the thing they use to sustain their work. Curie uses radium for research. Spinoza grinds lenses to earn a living. Both bodies erode gradually. Both know (or should know) the risk. Neither stops.
Curie doesn't stop because the discovery is too important. Spinoza doesn't stop because he needs independence. He declines a professorship at Heidelberg. He won't depend on any institution. Lens grinding makes him free—free to think, free to write, beholden to no one.
The price of freedom is glass dust.
VII. Closing
This is the final essay of the third cycle.
The third cycle begins with Plato—"He Wasn't There That Day." Plato was absent when Socrates drank the hemlock. From that absence he grew an entire philosophy—the theory of Forms. He needed a world where Socrates could not be killed. He built a wall.
The third cycle ends with Spinoza—"There Was Never a Wall."
Eighteen essays. Eighteen people. From "constructs can be closed" to "there was never a wall."
What happened in between?
Hume said sand suffices. Schopenhauer said there's a beast below. Kierkegaard leapt. Turing bit the apple. Chekhov said nothing. Cantor saw infinity. Copernicus set his book down and left. Quine said there is no such line. Beauvoir held up the mirror. Tesla heard the hum. Edison's light came on for a second, then went out. Heisenberg was uncertain. Bohr said the other side too. Tolstoy held out a prescription he couldn't swallow. Shakespeare was not there.
Then Spinoza arrives. He says one sentence. The quietest sentence. The largest sentence.
There was never a wall.
VIII. Grinding Lenses (Continued)
He ground lenses his entire life.
What are lenses for? They let you see what you otherwise cannot. Telescopes show you distant stars. Microscopes show you nearby cells.
He grinds lenses. He also writes the Ethics. The two activities are one. Lenses let you see what is physically invisible. The Ethics lets you see what is conceptually invisible—the single Substance, the thing everything is within, the world where there was never a wall.
Grinding lenses killed him. Writing the Ethics gave life to a world.
IX. One Thing
February 21, 1677. The Hague.
Spinoza dies. Forty-four years old.
After his death, his friends publish the Ethics. The book is immediately banned. Condemned as atheism. Deemed dangerous.
Two centuries later it is resurrected. Hegel calls Spinoza "the starting point of all modern philosophy." Goethe is captivated. Novalis calls him "the God-intoxicated man." When Einstein is asked whether he believes in God, he replies: "I believe in Spinoza's God."
His book lives. He is gone. Like Shakespeare.
On the bridge, one last figure. The final one.
He stands in the quietest position. Which position? Hard to say. Not because it is uncertain (Heisenberg)—because where he stands does not matter. In his world, all positions are different modes of the same thing. Standing here or there makes no difference.
His hands hold nothing. No apple (Turing). No bulb (Edison). No prescription (Tolstoy). No letter (Bohr). No formula (Heisenberg). No mirror (Beauvoir). No book (Copernicus).
In his hands, a trace of glass dust. Left over from grinding.
Socrates stands on cleared ground. Plato crouches, drawing plans. Hume plays billiards. Schopenhauer stares beneath the bridge. Kierkegaard leaps. Turing looks at the apple. Chekhov leans against the railing. Cantor gazes upward. Copernicus sets his book down and walks away. Sartre paces. Beauvoir holds the mirror. Quine says "there is no such line." Tesla listens to the hum. Edison holds the bulb. Heisenberg's position is indeterminate. Bohr holds the unsent letter. Tolstoy holds the prescription. Shakespeare is not there—he is the water beneath the bridge.
Spinoza looks at all of them.
What does he see?
He sees one thing. Not many people standing on a bridge. One thing. The bridge is it. The water is it. The people are it. The apple is it. The bulb is it. The prescription is it. The mirror is it. The formula is it. The silence is it. The hum is it. The waiting is it. The leaving is it too.
One thing.
He bends down. He blows the glass dust from his hands. The dust settles on the bridge. On everyone. Very fine. Almost invisible.
Deus sive Natura.
Then he straightens. He says nothing.
The third cycle is finished.[1][2]
Notes
[1]: Spinoza as "there was never a wall" and its relation to the chisel-construct cycle and "constructs cannot be closed" in Self-as-an-End theory: for the core argument, see the series methodology paper (DOI: 10.5281/zenodo.18842450). Spinoza closes the third cycle: Plato opens it ("constructs can be closed"), sixteen essays chisel the wall from various directions, Spinoza closes it ("there was never a wall"). His Deus sive Natura (God or Nature) is the most thoroughgoing "there is no such line"—not that the line has been broken, but that there was only ever one thing. Multi-layered parallel with Quine (epistemology), Heisenberg (physics), Nishida (ontology), Bohr (physical interpretation), and now Spinoza (metaphysics)—five levels, one insight. Spinoza is more radical than the others: he does not say "the line cannot be drawn"; he says "why would you draw a line?" Relation to Kant/SAE: Kant says the thing-in-itself is unknowable; SAE says not closable but approachable; Spinoza says you are already there—the curtain does not exist. Contrast with Tolstoy: Tolstoy restrains desire by willpower (prescription); Spinoza dissolves desire by understanding (geometry). Lens grinding = maintaining independence (declining the Heidelberg chair), and also being killed by one's trade—same structure as Curie being killed by her own discovery.
[2]: Spinoza's biography draws primarily on Steven Nadler, Spinoza: A Life (1999) and Roger Scruton, Spinoza: A Very Short Introduction (2002). Born in Amsterdam (November 24, 1632), Portuguese-Jewish family (Marranos). Excommunication from the Jewish community (July 27, 1656); text of the decree per Amsterdam Municipal Archives. "Baruch" to "Benedictus" per Nadler. Lens-grinding trade per multiple biographies. Declined Heidelberg professorship (1673) per Nadler. Deus sive Natura (God or Nature) per Ethics, Part IV Preface; see also the Stanford Encyclopedia of Philosophy entry. Ethics (Ethica Ordine Geometrico Demonstrata), written in geometric method, published posthumously 1677. Natura naturans / Natura naturata distinction per Ethics, Part I. Theological-Political Treatise (Tractatus Theologico-Politicus, 1670). Hegel's "the starting point of all modern philosophy" per Hegel's Lectures on the History of Philosophy. Novalis's "God-intoxicated man" per Novalis, Blütenstaub. Einstein's "I believe in Spinoza's God" per 1929 telegram to Rabbi Herbert S. Goldstein. Spinoza's death (February 21, 1677, The Hague), lung disease likely related to glass dust from lens grinding. Eighteenth essay, third cycle (closing essay). First fifty-eight essays at nondubito.net.