---
title: "2 Greenhouse Effect Quotes By Carl Sagan"
description: "2 Greenhouse Effect quotes by Carl Sagan. Plus more from Carl Sagan and more Greenhouse Effect sayings from other authors."
image: "https://sms4smile.com/quotes/i/da3/carl-sagan-160_blue-planet_the-principal-energy-sources-of-our-pres_1126507.jpg"
---

> [“The principal energy sources of our present industrial civilization are the so-called fossil fuels. We burn wood and oil, coal and natural gas, and, in the process, release waste gases, principally CO2, into the air. Consequently, the carbon dioxide content…](https://sms4smile.com/quotes/carl-sagan/the-principal-energy-sources-of-our-present-industrial-civilization/)

[Carl Sagan](https://sms4smile.com/quotes/author/carl-sagan/)

[Image](https://sms4smile.com/quotes/i/da3/carl-sagan-160_blue-planet_the-principal-energy-sources-of-our-pres_1126507.jpg)

> [If the greenhouse effect is a blanket in which we wrap ourselves to keep warm, nuclear winter kicks the blanket off.](https://sms4smile.com/quotes/carl-sagan/if-the-greenhouse-effect-is-a-blanket-in-which-we-wrap-ourselves-to/)

[Carl Sagan](https://sms4smile.com/quotes/author/carl-sagan/)

[Image](https://sms4smile.com/quotes/i/bcd/carl-sagan-160_blanket_if-the-greenhouse-effect-is-a-blanket-in_2996284.jpg)

## More by Carl Sagan

> [It is sometimes said that scientists are unromantic, that their passion to figure out robs the world of beauty and mystery. But is it…](https://sms4smile.com/quotes/carl-sagan/it-is-sometimes-said-that-scientists-are-unromantic-that-their/)

[Carl Sagan](https://sms4smile.com/quotes/author/carl-sagan/)

> [The prediction of nuclear winter is drawn not, of course, from any direct experience with the consequences of global nuclear war, but rather from…](https://sms4smile.com/quotes/carl-sagan/the-prediction-of-nuclear-winter-is-drawn-not-of-course-from-any/)

[Carl Sagan](https://sms4smile.com/quotes/author/carl-sagan/)

> [The suppression of uncomfortable ideas may be common in religion or in politics, but it is not the path to knowledge; it has no…](https://sms4smile.com/quotes/carl-sagan/the-suppression-of-uncomfortable-ideas-may-be-common-in-religion-or/)

[Carl Sagan](https://sms4smile.com/quotes/author/carl-sagan/)

> [“Telepathy’ literally means to feel at a distance, just as ‘telephone’ is to hear at a distance and ‘television’ is to see at a…](https://sms4smile.com/quotes/carl-sagan/telepathy-literally-means-to-feel-at-a-distance-just-as-telephone-is/)

[Carl Sagan](https://sms4smile.com/quotes/author/carl-sagan/)

> [“On the scale of worlds—to say nothing of stars or galaxies—humans are inconsequential, a thin film of life on an obscure and solitary lump…](https://sms4smile.com/quotes/carl-sagan/on-the-scale-of-worlds-to-say-nothing-of-stars-or-galaxies-humans-are/)

[Carl Sagan](https://sms4smile.com/quotes/author/carl-sagan/)

> [Every one of us is, in the cosmic perspective, precious. If a human disagrees with you, let him live. In a hundred billion galaxies,…](https://sms4smile.com/quotes/carl-sagan/every-one-of-us-is-in-the-cosmic-perspective-precious-if-a-human/)

[Carl Sagan](https://sms4smile.com/quotes/author/carl-sagan/)

> [In our time, we have sifted the sands of Mars, we have established a presence there, we have fulfilled a century of dreams!](https://sms4smile.com/quotes/carl-sagan/in-our-time-we-have-sifted-the-sands-of-mars-we-have-established-a/)

[Carl Sagan](https://sms4smile.com/quotes/author/carl-sagan/)

> [ “\[ When a religious couple wrote to Sagan about fulfilled prophecies, he wrote back in May 1996 :\] If ‘fulfilled prophecy’ is your criterion,… ](https://sms4smile.com/quotes/carl-sagan/when-a-religious-couple-wrote-to-sagan-about-fulfilled-prophecies-he/)

[Carl Sagan](https://sms4smile.com/quotes/author/carl-sagan/)

> [Don't judge everyone else by your own limited experience.](https://sms4smile.com/quotes/carl-sagan/don-t-judge-everyone-else-by-your-own-limited-experience/)

[Carl Sagan](https://sms4smile.com/quotes/author/carl-sagan/)

> [“Books permit us to voyage through time, to tap the wisdom of our ancestors. The library connects us with the insight and knowledge, painfully…](https://sms4smile.com/quotes/carl-sagan/books-permit-us-to-voyage-through-time-to-tap-the-wisdom-of-our/)

[Carl Sagan](https://sms4smile.com/quotes/author/carl-sagan/)

> [We live on a hunk of rock and metal that circles a humdrum star that is one of 400 billion other stars that make…](https://sms4smile.com/quotes/carl-sagan/we-live-on-a-hunk-of-rock-and-metal-that-circles-a-humdrum-star-that/)

[Carl Sagan](https://sms4smile.com/quotes/author/carl-sagan/)

> [A tiny blue dot set in a sunbeam. Here it is. That's where we live. That's home. We humans are one species and this…](https://sms4smile.com/quotes/carl-sagan/a-tiny-blue-dot-set-in-a-sunbeam-here-it-is-that-s-where-we-live-that/)

[Carl Sagan](https://sms4smile.com/quotes/author/carl-sagan/)

> [Any sufficiently crisp question can be answered by a single binary digit-0 or 1, yes or no.](https://sms4smile.com/quotes/carl-sagan/any-sufficiently-crisp-question-can-be-answered-by-a-single-binary/)

[Carl Sagan](https://sms4smile.com/quotes/author/carl-sagan/)

> [Humans — who enslave, castrate, experiment on, and fillet other animals — have had an understandable penchant for pretending animals do not feel pain.…](https://sms4smile.com/quotes/carl-sagan/humans-who-enslave-castrate-experiment-on-and-fillet-other-animals/)

[Carl Sagan](https://sms4smile.com/quotes/author/carl-sagan/)

> [Every star may be a sun to someone.](https://sms4smile.com/quotes/carl-sagan/every-star-may-be-a-sun-to-someone/)

[Carl Sagan](https://sms4smile.com/quotes/author/carl-sagan/)

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