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Revision as of 03:05, 4 September 2013

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Listen, in a few thousand years you'll invent a game called 'SimCity' which has a 'disaster' button, and then you'll understand.
Title text: Listen, in a few thousand years you'll invent a game called 'SimCity' which has a 'disaster' button, and then you'll understand.


This comic about rainbows coincided with the first release of a what if? in almost two months. It was called Tatooine Rainbow about rainbows if Earth had two suns like the fictive planet Tatooine from Star Wars.

In this comic the patriarch Noah, from the Abrahamic religions represented by Cueball, talks to God after the biblical flood. He asks what the coloured band across the sky is, and God tells him it is a rainbow. According to the Book of Genesis, God placed the worlds first rainbow in the sky as a promise to humanity that he would never again make a flood to cleanse the world of sin (Genesis 9:2–17). A rainbow is an optical phenomenon caused by reflection, refraction and dispersion of light in water droplets resulting in a spectrum of light appearing in the sky, one of many light phenomena caused by sunlight and precipitation.

Then Noah notices a double rainbow outside the original promise rainbow. Secondary rainbows are caused by double reflection of sunlight inside the raindrops. When asked about this God seems to falter, but recovers and claims he made it to show that he will never again set the Earth on fire. As an afterthought he says sorry about that, although it was a while back. This may refer to the early Earth being a liquid ball of molten rock (the Hadean period), or later global fire catastrophes caused by asteroid impacts and volcanic eruptions. That God promises to never again burn the earth goes against the idea of Armageddon where everything will be destroyed in fire etc.

Noah begins to notice some other optical phenomena, first he spots a halo. Halos can appear around the Sun (as is the case here) or the Moon. The one he spots is most likely the circular 22° halo, which is a halo forming a circle with a radius of approximately 22° around the Sun, or occasionally the Moon. God promptly claims it is a promise to never again make raccoons immortal as it destroyed the Earth's ecosystem. Although today these animals can be a pest, see 1565: Back Seat, they are luckily not immortal. Randall is likely referring to an unkillable form of immortality rather than biological immortal as while that would likely cause some issues, the raccoons can still fall to predation and disease. Should raccoons have been rendered unkillable by predation or disease as well as aging then the combination of an average gestational period of 65 days, a litter size of 2-5 individuals, and an omnivorous appetite makes for a creature that could easily dominate any and all ecological niches.

Noah continues by noticing two sun dogs (or parahelia) which often co-occur with the 22° halo. These consist of a pair of bright spots either side on the Sun, intersected by the halo. God gets tired of this and tries to stop Noah by saying that he has said sorry, and asks him to drop the subject. That is probably sensible because there are 23 different atmospheric optical phenomena listed on Wikipedia alone. Following the logic of the comic and the evasive answer of God, it could mean there are some more skeletons in the closet.

There are also "tertiary rainbow" (and even higher orders), which forms a ring around the sun, but this is normally lost in the glare of the sunlight passing through raindrops. These higher order rainbow (up to fifth order) are mentioned in the what if? referenced above. As it is halos that have sun dogs, and as these higher order rainbows are almost impossible to see with the naked eye, it is highly unlikely that it was supposed to be such a tertiary rainbow that Noah sees in the third panel.

The title text is a continuation where God tells Noah that in the future humanity will invent a game called SimCity. This is a strategy computer game in which the player creates and manages an environment wherein sims autonomously build a city (or in later versions a country, or a planet). The sims are simple AI processes that "build" residential, commercial and industrial structures within the game space, according the topography and zoning choices made by the player, then use them to create more wealth to expand their city. The sims have to contend with traffic jams, social problems, and ecological impacts of their own activity, and occasional natural disasters ranging from earthquakes to Godzilla.

The player has God-like control of the world, including a disaster button, for when the player doesn't want to wait for a disaster to happen by chance. God (in the xkcd comic) is suggesting that it is too tempting, once a civilization has been built up, to push the disaster button just to see what happens.

Overall the comic pokes fun at the idea of explaining natural phenomena as messages from a deity.


[Noah, here represented as Cueball, is looking up on a rainbow band going through the top right corner of the panel. The band displays the following colors from outward and in: Red, yellow, green, blue and purple. A black blob in the bottom of the panel right of Noah, has white text with the reply from God to Noah's questions. This continues through the rest of the comic.]
Noah: Wow, God- What's that band of color?
God: A rainbow.
God: It is a sign of my promise that I will never again flood the Earth.
[In this frameless panel Noah is not looking so much up. God's reply is split in two black blobs with a small connection between them.]
Noah: Oh, good! Hey, what about that second bow above the first one?
God: Oh, uh, sign of my promise not to set the earth on fire.
God: Sorry for doing that a while back.
[Noah points left, God's black reply blob hangs higher, only above Noah's shoulders]
Noah: What about that third faint bow near the sun?
God: My promise to never again destroy Earth's ecosystem by making raccoons immortal.
[Noah points even higher up towards left, with God's reply situated as before]
Noah: And the little rainbow clouds on either side of-
God: Look, I said I'm sorry. Can we just drop it?

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