Obsidian - Sharpen your thinking

Your thoughts are yours.: Obsidian stores notes on your device, so you can access them quickly, even offline. No one else can read them, not even us.
Your mind is unique.: With hundreds of plugins and themes, you can shape Obsidian to fit your way of thinking.
Your knowledge should last.: Obsidian uses open, non-proprietary files, so you're never locked in, and can preserve your data for the long term.

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Spark brilliance.

From personal notes to journaling, knowledge bases, and project management, Obsidian gives you the tools to come up with ideas and organize them.

Links: Create connections between your notes. Link anything and everything — ideas, people, places, books, and beyond. Invent your own personal Wikipedia.

In Meditations on First Philosophy the philosopher René Descartes describes a series of doubts about the nature of reality, arriving at the famous phrase:

[[I thin]]

I think therefore I am
Just think about it
Thinking, Fast and Slow
Books/
The Thing
Movies/

He argues that doubting requires thinking, and therefore, the act of thinking confirms his existence.

Graph: Visualize the relationships between your notes. Find hidden patterns in your thinking through a visually engaging and interactive graph.

Canvas: An infinite space to research, brainstorm, diagram, and lay out your ideas. Canvas is a limitless playground for your mind. Learn more.

Lecture 1

Rationalists

Reason and innate knowledge → acquire knowledge
Fundamental truths and principles can be known independent of experience
A priori reasoning
Reason and deduction

Empiricists

Experience and sensory perception → acquire knowledge
All knowledge is derived from experience and observation of the external world
A posteriori reasoning

Cogito, ergo sum

In Meditations on First Philosophy the philosopher René Descartes describes a series of doubts about the nature of reality, arriving at the famous phrase:

I think therefore I am

He argues that doubting requires thinking, and therefore, the act of thinking confirms his existence.

Philosophers

Image of Rene Descartes embedded in Obsidian Canvas

Image of Baruch Spinoza embedded in Obsidian Canvas

Wikipedia page about David Hume embedded in Obsidian Canvas

Plugins: Build your ideal thinking space. With hundreds of plugins and our open API, it's easy to tailor Obsidian to fit your personal workflow. Learn more.

Community plugins

Calendar by Liam Cain

Calendar view of your daily notes.

Kanban by Matthew Meyers

Markdown-backed kanban boards.

Dataview by Michael Brenan

Advanced queries for the data-obsessed.

Outliner by Viacheslav Slinko

Work with your lists.

Tasks by Martin Schenck and Clare Macrae

Track tasks across your entire vault.

Publish instantly.

Turn your notes into an online wiki, knowledge base, documentation, or digital garden. Learn more.

Seamless editing: Publish your notes instantly from the Obsidian app, and make it easy for readers to explore your web of ideas.
Customization: Control the look and feel of your site with themes, custom domains, password protection, and more.
Optimized for performance: Obsidian Publish sites are fast, mobile-friendly, and optimized for SEO, no configuration required.

Example of Obsidian Help site powered by Obsidian Publish

Explore the Obsidian Help site, powered by Obsidian Publish.

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