introduction to astronomy

List of Free Science Books

Here’s an alphabetical list of all available free books. Note that many of the links will bring you to an external page, usually with more info about the book and the download links. Also, the links are updated as frequently as possible, however some of them might be broken. Broken links are constantly being fixed. In case you want to report a broken link, or a link that violates copyrights, use the contact form


  • A Beginner’s Guide to Mathematica
  • A Brief Introduction to Particle Physics
  • A First Course in General Relativity
  • A New Astronomy
  • A No-Nonsense Introduction to General Relativity
  • A Popular History of Astronomy During the Nineteenth Century, Fourth Edition
  • A Review of General Chemistry
  • A Simple Guide to Backyard Astronomy
  • A Text Book for High School Students Studying Physics
  • A Tour of Triangle Geometry
  • About Life: Concepts in Modern Biology
  • Acoustic Emission
  • Adaptive Control
  • Advanced Calculus
  • Advanced Learning
  • Advanced Mathematics for Engineers
  • Advanced Microwave Circuits and Systems
  • Advanced Technologies
  • Advances in Computer Science and IT
  • Advances in Evolutionary Algorithms
  • Advances in Geoscience and Remote Sensing
  • Advances in Haptics
  • Advances in Human Computer Interaction
  • Age of Einstein
  • Aging by Design
  • AMPL:  A Modeling Language for Mathematical Programming
  • An Introduction to Elementary Particles
  • An Introduction to Higher Mathematics
  • An Introduction to Many Worlds in Quantum Computation
  • An Introduction to Mathematical Reasoning
  • An Introduction to Mathematics
  • An Introduction to Proofs and the Mathematical Vernacular
  • An Introduction to Relativistic Quantum Mechanics
  • Analysis 1 (Tao T)
  • Analysis 2 (Tao T)
  • Analytic Functions
  • Astronomical Discovery
  • Astronomy for Amateurs
  • Astronomy Today
  • Astronomy with an Opera-Glass
  • Automation and Robotics


  • Basic Algebra, Topology and Differential Calculus
  • Basic Concepts of Mathematics
  • Basic Concepts of Thermodynamics
  • Basic Concepts of Thermodynamics Chapter 1
  • Basic Ideas in Chemistry
  • Basic Math: Quick Reference eBook
  • Basic Mathematics for Astronomy
  • Basic Physics
  • Basic Positional Astronomy
  • Basic Principles of Classical and Statistical Thermodynamics
  • Basic Principles of Physics
  • Basics of Physics
  • Beginner’s Botany
  • Biochemistry
  • Biochemistry (practice book)
  • Biology
  • Board Notes for Particle Physics
  • Book of Proof


  • Calculus
  • Calculus Based Physics
  • Celestial Navigation, Elementary Astronomy, Piloting
  • Circuit QED — Lecture Notes
  • Classical Dynamics
  • Classical Geometry
  • Classical Mechanics
  • Climate Models
  • Collaborative Statistics
  • College Algebra
  • Complex Analysis
  • Computational Geometry
  • Computational Introduction to Number Theory and Algebra
  • Computational Physics with Python
  • Conceptual Physics
  • Consistent Quantum Theory
  • Cook-Book Of Mathematics
  • College Physics
  • Crude Oil Emulsions- Composition Stability and Characterization
  • Curiosities of the Sky


  • Decoherence: Basic Concepts and Their Interpretation
  • Do We Really Understand Quantum Mechanics?
  • Differential Equations
  • Diophantine Analysis
  • Discover Physics
  • Dr. Donald Luttermoser’s Physics Notes
  • Dynamics and Relativity


  • Earthquake Research and Analysis
  • Earthquake-Resistant Structures – Design, Assessment and Rehabilitation
  • Einstein for Everyone
  • Electromagnetic Field Theory
  • Elementary Mathematical Astronomy
  • Elementary Linear Algebra
  • Elementary Particle Physics in a Nutshell
  • Elementary Particles in Physics
  • Elements of Astrophysics
  • Embedded Systems – Theory and Design Methodology
  • Encyclopaedia of Mathematics
  • Encyclopedia of Astrophysics
  • Engineering Mathematics 1
  • Engineering Mathematics with Tables
  • Essential Engineering Mathematics
  • Essential Physics
  • Exoplanet Observing for Amateurs
  • Experimental Particle Physics


  • Fields
  • Foundations of Nonstandard Analysis
  • Frequently Asked Questions about Calendars
  • Fundamental Concepts of Mathematics
  • Fundamentals of Analysis (Chen W.W.L)
  • Further Mathematical Methods
  • Fusion Physics


  • General Chemistry
  • General Relativity
  • General Relativity
  • Geometric Asymptotics
  • Geometry and Group Theory
  • Geometry and Topology
  • Geometry Formulas and Facts
  • Geometry Study Guide
  • Geometry, Topology and Physics
  • Geometry, Topology, Localization and Galois Symmetry
  • Great Astronomers


  • Handbook of Formulae and Physical Constants
  • High School Mathematics Extensions
  • Higher Mathematics for Engineers and Physicists
  • History of Astronomy
  • Homeomorphisms in Analysis
  • How to Use Experimental Data to Compute the Probability of Your Theory


  • Intelligent Systems
  • Intrinsic Geometry of Surfaces
  • Introduction to Astronomy and Cosmology
  • Introduction to Cancer Biology
  • Introduction to Chemistry
  • Introduction to Cosmology
  • Introduction to Elementary Particles
  • Introduction to General Relativity
  • Introduction To Finite Mathematics
  • Introduction to Particle Physics Notes
  • Introduction to PID Controllers
  • Introduction to Quantum Mechanics with Applications to Chemistry
  • Introduction to Quantum Noise, Measurement and Amplification
  • Introduction to Social Network Methods
  • Introduction to String Field Theory
  • Introduction to the Time Evolution of Open Quantum Systems
  • Introduction to Quantum Mechanics
  • Introductory Computational Physics
  • Introductory Physics 1
  • Introductory Physics 2


  • Kinetic Theory


  • Laboratory Manual for Introductory Physics
  • Laws of Physics
  • Learn Physics Today
  • Lecture Notes in Discrete Mathematics
  • Lecture Notes in Quantum Mechanics
  • Lecture Notes in Nuclear and Particle Physics
  • Lecture Notes in Particle Physics
  • Lecture Notes on General Relativity
  • Lectures on Astronomy, Astrophysics, and Cosmology
  • Lectures on Particle Physics
  • Lectures on Riemann Zeta-Function
  • Light and Matter


  • Mag 7 Star Atlas Project
  • Many Particle Physics
  • Math Alive
  • Mathematical Analysis I(Zakon E)
  • Mathematical Biology
  • Mathematical Methods
  • Mathematical Methods 1
  • Mathematical Methods for Physical Sciences
  • Mathematical Methods of Engineering Analysis
  • Mathematics, Basic Math and Algebra
  • Mathematics for Computer Science
  • Mathematics for Computer Science
  • Mathematics for Computer Scientists
  • Mathematics For Engineering Students
  • Mathematics Formulary
  • Motion Mountain
  • Music: A Mathematical Offering
  • Mysteries of the Sun


  • Natural Disasters
  • New Frontiers in Graph Theory
  • Noise Control, Reduction and Cancellation Solutions in Engineering
  • Nondestructive Testing Methods and New Applications
  • Nonlinear Optics
  • Notes on Coarse Geometry
  • Notes on Elementary Particle Physics
  • Notes on Quantum Mechanics


  • Observing the Sky from 30S
  • On Particle Physics
  • Operating Systems: Three Easy Pieces


  • Particle Physics Course Univ. Cape Town
  • Particle Physics Lecture Notes
  • People’s Physics Book
  • Perspectives in Quantum Physics: Epistemological, Ontological and Pedagogical
  • Photons, Schmotons
  • Physics Lectures
  • Physics Tutorials
  • Physics Study Guides
  • Pioneers of Science
  • Practical Astronomy
  • Practical Astronomy for Engineers
  • Preparing for College Physics
  • Primer Of Celestial Navigation
  • Principal Component Analysis – Multidisciplinary Applications
  • Publications of the Astronomical Society of the Pacific Volume 1


  • Quantum Dissipative Systems
  • Quantum Field Theory
  • Quantum Fluctuations
  • Quantum Information Theory
  • Quantum Magnetism
  • Quantum Mechanics
  • Quantum Mechanics
  • Quantum Mechanics: A Graduate Course
  • Quantum Mechanics: An Intermediate Level Course
  • Quantum Notes
  • Quantum Physics Notes
  • Quantum Theory of Many-Particle Systems
  • Quantum Transients


  • Recreations in Astronomy
  • Relativistic Quantum Dynamics
  • Relativity: The Special and General Theory
  • Review of Basic Mathematics
  • Riemann Surfaces, Dynamics and Geometry Course Notes


  • Short History of Astronomy
  • Sintering of Ceramics – New Emerging Techniques
  • Solitons
  • Some Basic Principles from Astronomy
  • Special Relativity
  • Spherical Astronomy
  • Star-Gazer’s Hand-Book
  • Statistical Physics
  • Street-Fighting Mathematics
  • String Theory
  • Structures of Life
  • Supernova Remnants: The X-ray Perspective
  • Superspace: One Thousand and One Lessons in Supersymmetry
  • System of Systems


  • The Astrobiology Primer: An Outline of General Knowledge
  • The Astronomy and the Bible
  • The Astronomy of the Bible: An Elementary Commentary on the Astronomical References of Holy Scripture
  • The Basic Paradoxes of Statistical Classical Physics and Quantum Mechanics
  • The Beginning and the End
  • The Beginning and the End of the Universe
  • The Complete Idiot’s Guide to the Sun
  • The Convenient Setting of Global Analysis
  • The Eightfold Way: The Beauty of Klein’s Quartic Curve
  • The General Theory of Relativity
  • The Geology of Terrestrial Planets
  • The Geometry of the Sphere
  • The Handbook of Essential Mathematics
  • The Moon: A Full Description and Map of its Principal Physical Features
  • The Open Agenda
  • The Origin of Mass in Particle Physics
  • The Particle Detector Brief Book
  • The Physics Hypertextbook
  • The Physics of Quantum Mechanics
  • The Planet Mars
  • The Small n Problem in High Energy Physics
  • The Story of Eclipses
  • The Story of the Heavens
  • The Structure of Life
  • The Wonder Book of Knowledge
  • The World According to the Hubble Space Telescope
  • The Zij as-Sanjari of Gregory Chioniades (June 27, 2009)
  • Three Dimensional Geometry


  • Understanding Physics
  • Unfolding the Labyrinth
  • Utility of Quaternions in Physics
  • Uses of Astronomy
how did i get here? pt. 1

so, as an introduction of sorts to the studyblr/gradblr/collegeblr community, i kind of wanted to go through a quick introduction of my undergrad experience. it’s still totally crazy to me that i’m going to grad school for planetary sciences in the fall, so maybe this is a little bit of an exercise in nostalgia as well.

i did my undergrad at columbia university. lovely place in new york city that’s far enough from downtown manhattan to feel a little homey, but in manhattan enough to feel like a city. 

(ID: Columbia’s campus on a particularly beautiful evening. The sky is painted with purples and yellows and oranges. There are a few people walking up and down the white marbley-stoney steps of the campus, as well across the red brick path adjacent to College Walk, cutting through the campus. A few academic-looking neoclassical buildings can be seen in the background. All the lights are just starting to turn on, and the campus feels tranquil.)

the one constant major i had throughout college was astrophysics. a lot of people talk about how so many people change what they do in college, but somehow, this didn’t happen for me. i knew i loved astrophysics, and the astronomy department at columbia was really lovely and supportive, and i found a niche there that i didn’t want to leave.

my first year, i was also a chemical physics major. i was really interested in polymers, nanoparticles, quantum chemistry, materials science, etc. my first summer - this was my first research opportunity ever - was spent in a chemical engineering lab working on click reactions of different polymers. and while i did enjoy what i was learning, i realized that the subject might not be for me.

i dropped the chemical physics major after i got screwed on my first orgo midterm during my sophomore fall. this involved a lot of crying, a lot of thinking i wasn’t ever going to be good enough to do things that were interesting to me, a lot of questioning if it was just my lack of perseverance, etc. but the one thing i learned during that time, and in the years afterwards, is that quitting is okay! i learned that, while i liked chemistry a lot, there was a subject i loved even more, and it was okay to pursue that in full.

i then picked up a computer science major in addition to astrophysics. this was done partly as an insurance policy for my family, who remained unconvinced that i could find any real career path in astronomy. but, weirdly, i ended up really loving parts of cs, and really enjoying the moments where i could apply things i learned in cs to my astrophysics work. i kept my cs major until senior year, where i had a….less than pleasant encounter with a machine learning professor who refused to let me take his class even though i needed it desperately to graduate on time. so, in a fit of rage and self-preservation, i dropped my cs major to a concentration (our version of a minor). i had done all the required classes, so i was able to chill out a bit senior year when i was applying to grad school, which was dope.

i think i realized i wanted to do research ~for real~ the fall of my senior year, when i was still applying to cs jobs. i was interviewing in SF for a job that i realized i really didn’t care that much about, and during dinner the day of that interview i just caught myself thinking about how sad i would be if i just let my love for astronomy go. i think, at that point, i really changed my perspective and viewed grad school not just as an option, but my first option. and somehow, some way, it worked out. i guess i’ll try to talk about that in later posts.

Following all Studyblrs

Hey there!

I’m a new studyblr and just to get things started I am following any studyblrs that reblog this post and/or follow me.


  • My name is Rowan
  • I’m from the West coast of Scotland and I live in Glasgow
  • I’m 18 years old
  • I’m going into my second year of University and I’m super excited but also full of dread and woe
  • My subject is Astronomy and Physics and I want to either work in Astronomy or do something totally unrelated
  • I’m an ENTP Gryffindor/Thunderbird 
  • I’m learning French, Spanish and BSL at the moment :D
  • The song stuck in my head right now is Left Hand Free by alt-J for some ungodly reason?
  • I’m a ToEFL English teacher to pay for food and booze


  • Space!!!! and Aliens!!!!
  • Binging netflix series and then forgetting everything about them
  • Mythology espec. Greek (cause I’m basic like that)
  • History :D Currently reading A Little History of Science, and vehemently ignoring the fact that I have three other books on the go (for the last 6 months) and a whole reading list to get through next year :L
  • I love painting and drawing, like a lot

This semester’s classes

  • Multivariable Calculus
  • Linear Algebra
  • Observational Astrophysics
  • Relativity and Gravitation
  • Newtonian Dynamics
  • Oscillating Systems
  • Thermal Physics and Physics of Solids

My goals

  • To own a Swiss Cheese plant and to love and cherish it every day
  • To go to the moon, or maybe just into orbit (I’m easily impressed)
  • To travel the whole world, or at least every continent
  • To learn 5 languages (at least one with a non-latin writing system)
  • To get my MSci and enjoy doing it!

Blogs that I love 

@emmastudies @sumastudies @thecoffeedesk @stvdybuddies @lawschoolstudying @elixirstudies @nerdastically @m-ediblr @imperialstudy @cayliestudies @bookmrk @sarxhstudies @alimastudies @estudier @barbie-studies

Looking forward to joining the studyblr community :D :D :D


Hey! It’s been a while since I have been active in this blog so I think it’s time to introduce myself.

> I’m Alondra (girl)

> I’m 16 years old

> I’m Mexican (so I speak spanish, if you are learning it and want to practice you can message me)

> I want to study International Business

> I’m a taurus, hufflepuff, ambivert 

> I love learning languages. Currently I’m learning Korean, German and English.

> I like K-pop and korean dramas (I’m a multifandom btw)

> I love cats, books, astronomy, chemistry and history!

> I joined this community because many studyblogs really inspired me! Thank you so much 🌙

> Some of my favorites studyblogs are (I really like a lot haha)

@equaticns , @calligr4phy , @kankenstudies , @studyign , @apricot-studies , @snowystudiess , @getstudyblr , @obsidianstudy , @merakinotes , @yomistudy , @studious-annabeth , @optomstudies , @studiesara , @sugaredstudies

(those are just some of the studyblogs I follow and like)

If you want to talk just message me! I really love making new friends. If you are a studyblog like/repost this so I can follow you! 🌙

Thank you so much for reading! I’m so happy to be part of this great community!

Hi everyone! Call me Faith. I’ve been slinking my way around the studyblr community for long enough, it’s about time I go ahead and participate. 

About me:

  • I’m a junior in university studying physics with engineering
  • I’m Hispanic (Cuban-Puerto Rican!)
  • I’m ENFP, Slytherin, Cancer… try finding that moodboard :P

Things I like:

  • Reading
    • Favourite book: The Count of Monte Cristo by Alexandre Dumas
    • Favourite Spanish-language author: Jorge Luis Borges
    • Favourite English-language author: Toni Morrison
  • Programming
    • Java, C++, Python, JavaScript
    • I’m working my way through the front-end development part of freeCodeCamp!
      • slowly…slowly…
    • I’d love to learn about programming for robotics, I’ve gotta get on that
  • Writing
    • Short stories are a way of life
    • Let’s see if this year’s the year for NaNoWriMo

Classes I’m taking:

  • Modern Astrophysics
  • Electromagnetism
  • Dynamics
  • Differential Equations


  • Learning assistant for physics 1
  • President of a club to encourage women in STEM
  • Tutor
  • Telescope operator at the school observatory

Some studyblrs I like:

@lattesatmidnight | @gradeinspiration | @motivationsforlife | @zeestudies | @emmastudies | @studying-slytherin-guy | @gudetama-studies | @badasstudies | @birdkostudies | @polcry | @dungeonstudy | @please-study | @classicalstudies | @kiyoko-studies | @realstudie | @studyflorals | @yume-studies | @studystylebr | @sleepystvdying | @studyingonpointe | @ravnclaw | @notquiteanengineer | @soymilkstudies | @tanakastudies

anonymous asked:

Hey just wondering if you recommend any books for people wanting to understand more about the fundamentals of astronomy.

I love these kind of questions, because it makes me think about writing a whole article. This topic - ASTRONOMY BOOKS - could be really beneficial for many people who want to start with the basics of astronomy, even for those who already started and want to deepen their knowledge.

This list of the best 3 astronomy books is not official, it is just my opinion mixed with my experiences :) Enjoy!

The Elegant Universe: Superstrings, Hidden Dimensions, and the Quest for the Ultimate Theory

~ by Brian Greene  

The international bestseller providing the new understanding of the universe introduces string and superstring theory, and provides a comprehensive though non-technical assessment of the theory and some of its shortcomings. The reader does not have to be an expert, it is also suitable for people who don´t know much about the physics and the universe, but still they can be a little confused. I recommend to read this book several times to make a bigger picture. But still - it is the best book I´ve ever read

Extra links

× Amazon

×More about the book

× Author Bio

NightWatch: A Practical Guide to Viewing the Universe

~ by Terence Dickinson

This book assumes that the reader has no prior experience with astronomy. It is clear and concise enough for any beginner to understand. It is a perfect introduction to astronomy and stargazing.
It contains everything you need to know about what’s up in the sky through the year 2025 and it is filled with star charts, tables with information about stargazing events and incredible photos of space. Also an entire chapter is dedicated to stargazing technology.
I recommend this book for absolute beginners.

Extra links

× Amazon

× Youtube

× Author Bio

The Physics Book: From the Big Bang to Quantum Resurrection, 250 Milestones in the History of Physics

~ by  Clifford A. Pickover

I´ve got this book for last Christmass and I highly recommend this book for those who just started to be curious about astronomy and physics and even for those who are already studying these subjects. This book offers a great view to the basics of physics mainly, but it also contains a few stuff about astronomy included in the top 250 milestones. Pickover is well-known author because of his two best sellers included this book and The Math Book: From Pythagoras to the 57th Dimension, 250 Milestones in the History of Mathematics. I would love to have another books of this author!

Extra links

× Amazon

× Other books of this author

× Author Bio

These are just top 3 books about astronomy and physics by my opinion, but there are plenty more. I don´t know a bad book about this topic. It is just difficult to realize which book is for beginners and which one is for much more experienced ones and then decide to read it or not.

This is a little longer list of my favourite astronomical books (I wrote it down as a part of my answer to another question >> here << )

~The Fabric of the Cosmos: Space, Time, and the Texture of Reality

~  The Book of Constellations: Discover the Secrets in the Stars

~  Pale Blue Dot: A Vision of the Human Future in Space

~  Cosmos

Hope I helped you a little and thank you for your question!
With love @astrophysicsstudent <3


Hannah M. Bouvier. Telescopic View of Venus, The Earth in her Orbit, Night and Day, Venus in her Orbit Around the Sun, The Meridian, Mars, Jupiter, Saturn, Telescopic View of the Moon, Rings of Saturn. Bouvier’s Familiar Astronomy. 1858.

The Jones Brothers fic: Adrift

I was supposed to be working on other things, but this decided to jump the queue. It is my attempt to connect dots in their background that I feel had no connection prior. Obviously, it’s not going to be a particularly happy tale. But it does set the stage for Killian’s later knack for navigation. 

Rating: PG-13 for child abuse (but nothing really horrific, I promise)

Word count: 2700

Summary: Sometimes the stars misalign. 


“How do you know where we’re going?” Killian asked.

He and Liam had been aboard the ship their father abandoned them to for a few months, and once he’d stopped expecting his father to come rescue them, he’d started paying attention to what was going on around him when he wasn’t being watched himself. He’d always dreamed of setting sail to see far-off lands, and his father’s promise of seeing the realms was coming true, but not in the way Killian ever imagined or wanted. He was learning what life aboard a ship was like, that was true, but he wanted to know more than the scut work.

The helmsman glanced over at the boy and sighed. “Shouldn’t you be tendin’ ta yer duties?”

“I’ve finished for the moment.”

Without looking at Killian, he said, “Then maybe ya oughter go help yer brother wi’ his.”

“Captain won’t let me.” Neither would Liam, but he wasn’t going to share that information. He was trying to keep from getting Liam into trouble by messing things up as he had several times already since their status changed from passenger to slave. He couldn’t stand watching another bruise bloom on his brother’s skin on account of his clumsiness.

Another sigh escaped the old sailor and he continued to ignore the boy. Killian wasn’t deterred. He watched as the man, Fulton, looked from the compass attached to the helm, to the horizon, then up at the sky. When he moved the wheel three spokes to the left—port—Killian thought he figured the answer out. 

Keep reading

When I look up at the night sky...I feel big.

“ The most astounding fact is the knowledge that the atoms that comprise life on Earth - the atoms that make up the human body are traceable to the crucibles that cooked light elements into heavy elements in their core, under extreme temperatures and pressures. These stars, the high mass ones among them went unstable in their later years they collapsed and then exploded scattering their enriched guts across the galaxy. Guts made of carbon, nitrogen, oxygen and all the fundamental ingredients of life itself. These ingredients become part of gas clouds that condense, collapse, form the next generation of solar systems. Stars with orbiting planets, and those planets now have the ingredients for life itself. So that when I look up at the night sky and I know that yes, we are part of this universe, we are in this universe, but perhaps more important than both of those facts is that the Universe is in us. When I reflect on that fact, I look up – many people feel small because they’re small and the Universe is big – but I feel big, because my atoms came from those stars. There’s a level of connectivity. That’s really what you want in life, you want to feel connected, you want to feel relevant you want to feel like you’re a participant in the goings on of activities and events around you That’s precisely what we are, just by being alive… “  - Neil deGrasse Tyson

One of the most influential classes I ever took in college was an Introduction to Astronomy course. I had no idea what I was in for…hands down one of the hardest subjects I ever experienced, but by far the most rewarding. There are few things I respect more than a brilliant teacher, because we forget how hard it can be to take a complex thought and break it down in to something the masses can understand. It’s beyond challenging. Which is why I am so thankful for having an extremely talented professor whose passion for Astronomy created a rippling effect throughout our entire classroom. As students, we left every night longing to know more. I remember watching people walk outside, it was a night course, which made it that much better. We would all look up and I distinctly recall the conversation I had with one of my peers about how we no longer felt insignificant or small when gazing at the vastness of the night sky. In fact, it was the exact opposite…deGrasse hits the nail on the head with this one, as he most always does. 

I described [the medievals] as literate people who had lost most of their books. And what survived was, to some extent, a chance collection. It contained ancient Hebrew, classical Greek, classical Roman, decadent Roman and early Christian elements. It had reached them by various routes. All Plato had disappeared except part of the Timaeus in a Latin version: one of the greatest, but also one of the least typical, of the dialogues. Aristotle’s logic was at first missing, but you had a Latin translation of a very late Greek introduction to it. Astronomy and medicine, and (later) Aristotle, came in Latin translations of Arabic translations of the Greek. That is the typical descent of learning: from Athens to Hellenistic Alexandria, from Alexandria to Baghdad, from Baghdad, via Sicily, to the university of Paris, and thence all over Europe…

A scratch collection, a corpus that frequently contradicted itself. But here we touch on a real credulity in the medieval mind. Faced with this self-contradictory corpus, they hardly ever decided that one of the authorities was simply wrong; never that all were wrong. To be sure, in the last resort it was taken for granted that the Christian writers must be right as against the Pagans. But it was hardly ever allowed to come to the last resort. It was apparently difficult to believe that anything in the books - so costly, fetched from so far, so old, often so lovely to the eye and hand, was just plumb wrong. No; if Seneca and St Paul disagreed with one another, and both with Cicero, and all these with Boethius, there must be some explanation which would harmonize them. What was not true literally might be true in some other sense; what was false simpliciter might be truesecundum quid. And so on, through every possible subtlety and ramification.

It is out of this that the medieval picture of the universe is evolved: a chance collection of materials, an inability to say ‘Bosh’, a temper systematic to the point of morbidity, great mental powers, unwearied patience, and a robust delight in their work. All these factors led them to produce the greatest, most complex, specimen of syncretism or harmonization which, perhaps, the world has ever known. They tidied up the universe.

—  C. S. Lewis on how Medieval scholars rationalized the available canon of philosophy and protoscience in the ancient world: from “Imagination and Thought in the Middle Ages”