Meditations On First Philosophy Summary

1-Sentence-Summary: Meditations On First Philosophy is one of the premier works of Western philosophy, written by René Descartes in 1641, prompting us to abandon everything that can possibly be doubted and then starting to reason our way forward based only on what we can know with absolute certainty.

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The first time I ever learned something more from René Descartes than “Cogito, ergo sum” (I think, therefore I am) was in 2014. One of the steps in Tai Lopez’s 67 Steps program was labeled “Descartes & Solving Problems With A Calculator.”

It explained how Descartes kept questioning himself for days: “Is this really true? Is there a 0.000000000000001% chance it isn’t?” And every time he found doubts, he removed a particular belief from his mind, until he eventually saw he was left with only one thing: math.

Meditations On First Philosophy shows how he reasoned his way to these conclusions and more. It’s one of the prime works of Western philosophy, written in 1641 and therefore part of any well-educated man’s (or woman’s) reference book.

Here are 3 lessons from Descartes:

  1. Your senses don’t always tell the truth.
  2. The fact that you think proves that you exist.
  3. There are three levels of truth in the world.

Feeling smart? Our philosophical plane ‘descartes’ now! (pun intended)

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Lesson 1: Don’t trust your senses without questioning them.

The first thing Descartes argues is that you can’t build your understanding and view of the world on lies. Therefore, anything that can be doubted in even the slightest way must be abandoned in favor of the truth.

Approaching life with a healthy dose of skeptical doubt means first not believing everything your senses tell you. Just imagine what it’s like to dream. Dreams are vivid, you can feel things in them, taste food and even pain seems real – yet when you wake up, none of it all has happened.

Similarly, mythical creatures like the minotaur, unicorns and mermaids sure seem unlikely, but don’t you still believe in them at least a little?

Fake pics and videos circulate the internet and thousands of U.F.O. sightings have been debunked over the years. Just think of The Matrix or The Truman Show (or how some animals try to lure others into traps with seductive scents) and you’ll instantly agree that not everything you see, hear and feel is real.

Lesson 2: The ability to think is the best proof of existence.

This is where Descartes most famous line “I think, therefore I am” comes in. Given that all things our senses tell us can be doubted, what’s even left?

According to Descartes, the one thing we can rely on is knowing that as long as you think, you truly exist. Even if your nose tells you that there’s an apple pie smell coming from around the corner, by thinking about it you can challenge this. Whether the apple pie really exists, or is actually something else, or even just part of a dream – the fact that you think about the apple pie proves that you exist.

Whatever our brain perceives, true or not, and can make judgments about, is further proof for our own existence. That’s why as long as you think, you exist and are alive. So much for you being a true thing, but what about all the other stuff in the world?

Lesson 3: Everything in the world can be put into one of three categories of truth.

Okay, so your brain is reliable, but your senses aren’t. That leaves us with three different levels of truth then:

  1. The truth of things you can explain using only your mind.
  2. The truth of things you can explain by using your senses.
  3. The truth of things you can explain with a mix of your mind and senses.

Descartes says the first level is the most sound, simply because thinking is our most reliable asset. That’s why math, a sole construct of the mind, for example, is so utterly rational. By combining mind-constructs like math, astronomy, geometry, we can even derive knowledge about far-away objects like the sun, for example the fact that it’s a huge, round star.

Level two truths are less reliable, because they rely on our faulty senses. For example, if you thought the sun was very small, simply because you see it only as a small object in the sky, you’d sure be in for a surprise if you ever went there.

Lastly, everything where mind and senses mix to explain something based on a combination of our own ideas, like hippogriffs, fairies and dragons, is usually quite far from the truth. These level three “truths” have a small degree of reality.

The next time you doubt something, try to think which category it goes into!

Meditations On First Philosophy Review

For books like these I’m glad to have a set of blinks, Wikipedia articles, etc. to consult – simply because the original texts are super complicated. I’d still love to get a modern translation of Meditations On First Philosophy though, there’s a ton of things to learn from and make you a better thinker in philosophical works like this one.

Little quirk: When Descartes was close to despair from all his thinking, he’d resort to the recently invented calculator (adding machine, created by Blaise Pascal in 1642), for he could always find consolation in the truth of math.

Who would I recommend the Meditations On First Philosophy summary to?

The 16 year old who struggles with math in school, the 47 year old atheist, who thinks life isn’t worth working hard, because we’ll all die anyway, and anyone who loves adding numbers with a calculator.

Last Updated on January 25, 2023

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Niklas Göke

Niklas Göke is an author and writer whose work has attracted tens of millions of readers to date. He is also the founder and CEO of Four Minute Books, a collection of over 1,000 free book summaries teaching readers 3 valuable lessons in just 4 minutes each. Born and raised in Germany, Nik also holds a Bachelor’s Degree in Business Administration & Engineering from KIT Karlsruhe and a Master’s Degree in Management & Technology from the Technical University of Munich. He lives in Munich and enjoys a great slice of salami pizza almost as much as reading — or writing — the next book — or book summary, of course!