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+# Pantheon Generator
+
+This library procedurally generates `Gods` with internally-coherent domains,
+and `Pantheons` comprising generations of `Gods` that feel related to one
+another. To achieve a good mix of cohesiveness and novelty, it employs the
+metaphor of sexual reproduction:
+
+* Words are **chromosomes**.
+* A **genome** is a list of 46 words.
+* A **gamete** (an egg or sperm) is a list of 23 words.
+* A **gene pool** is a list of tokens drawn from different texts.
+* **Asexual reproduction** occurs when a user generates a `God` from two strings.
+* **Sexual reproduction** occurs when a user generates a `Pantheon` from two `Gods`.
+
+### How to Use the Library
+
+The user selects two seed words and uses them to generate a `God`:
+
+> God("hunting", "art")
+
+The result is Chetan, God of Illustrators, Prints, and Drawings. The user does
+this a second time:
+
+> God("agriculture", "science")
+
+The result is Kapilla, Goddess of Orchards and Schools. The user combines these
+two `Gods` to generate a `Pantheon`:
+
+> Pantheon(Chetan, Kapilla)
+
+The deities reproduce for several generations. The result in a `Pantheon` with a
+few dozen `Gods` in it. One of these is Ajit, Demi-God of Talents, Crafts, and
+Prancing.
+
+
+
+# Models
+
+### Attributes of a `God`
+
+* **chromosomes**: Either `XX` or `XY`.
+* **gender**: Either `male`, `female`, or `non_binary`.
+* **genome**: A list of up to 46 words.
+* **generation**: An integer set during a `pantheon.spawn()`.
+* **divinity**: Either `god`, `demi_god`, or `human`.
+* **name**: A string pulled at random from a list of `female_names`, `male_names`, or `nb_names`.
+* **epithet**: A string that combines a title (God, Goddess, Divine Being, ...) with between 1 and 4 domains. A domain is a word randomly selected from the `God's` genome. Example: Goddess of hunting and war.
+* **parents**: The `Gods` whose egg and sperm combined to create this `God`.
+
+### Attributes of a `Pantheon`
+
+* **gods**: A dictionary mapping names to `Gods`.
+
+# Reproduction
+
+### Spawning [Gods](https://github.com/carawarner/pantheon/blob/master/scripts/gods.py)
+
+Given two `Gods`, one `XX` **egg donor** and one `XY` **sperm donor**...
+
+1. Select a random word from the `God.genome` of the **egg donor**.
+1. Use spaCy to pull 23 related words from the **gene pool**. This is the **egg**.
+1. Select a random word from the `God.genome` of the **sperm donor**.
+1. Use spaCy to pull 23 related words from the **gene pool**. This is the **sperm**.
+1. Add the **egg** and **sperm** together. This list of 46 words is the *genome* for the new `God`.
+
+_Note: because a `God's` genome is populated with words **related** to seeds from its parents' genomes, a `God` feels **genetically related** to its parents. But, because the seeds are selected at **random** from the parents' genomes, there's room for **genetic drift**._
+
+### Spawning [Pantheons](https://github.com/carawarner/pantheon/blob/master/scripts/pantheons.py)
+
+Given two `Gods`, one `XX` **egg donor** and one `XY` **sperm donor**, and a number of generations **N**...
+
+1. Declare a list of **egg donors** and a list of **sperm donors**.
+1. Iterate **N** times, once for each generation...
+1. At the start of each generation breed the **egg donors**.
+1. At the end of each generation, add mature offspring to the breeding pool.
+1. At the end of each generation, remove elder `Gods` from the breeding pool.
+
+
+# Code Imitating Nature
+
+The model blends randomness and probability to echo the beauty of nature.
+
+**[Gender](https://github.com/carawarner/pantheon/blob/master/scripts/gods.py#L26-L35)**: There's a 7% chance a `God` will be transgendered and a 3% chance a `God` will be non-gendered or gender-queer. For this reason the model refers to 'egg donors' and 'sperm donors' not 'mothers' and 'fathers'. Two male `Gods` can procreate, as can two female `Gods`, or a gender-queer `God` and another `God`, as long as one parent is `XX` and one is `XY`.
+
+**[Sex](https://github.com/carawarner/pantheon/blob/master/scripts/gods.py#L57)**: When a new `God` spawns, its sex chromosomes are chosen at random. It's possible for several `Gods` in a row to be `XX` or `XY`. An unexpected consequence of this: some Pantheons grow much faster than others. The rate of growth is determined by the number of `XX` gods born in each generation.
+
+**[Mutation](https://github.com/carawarner/pantheon/blob/master/scripts/gods.py#L170-L172)**: The related words that spaCy finds in a list of plural nouns often feel "more related" than the ones it finds in a list of gerunds. This is just something I observed. 80% of the time this model pulls gametes from `primary_tokens`, which is a list of NNS; the other 20% of the time it pulls gametes from `secondary_tokens`, which is a list of VBG. The result is some children look a lot like their parents and some look very different; there's variety in how far the apple falls from the tree.
+
+**[Power Level](https://github.com/carawarner/pantheon/blob/master/scripts/gods.py#L12-L24)**: Many traditions describe old gods as more powerful than young gods. When two `Gods` procreate there's a 30% chance their offspring will be a 'demi-god' rather than a full blown god. That chance jumps to 50% when a 'god' and 'demi-god' procreate, and when two 'demi-gods' procreate there's a 25% chance their offspring will be a lowly human.
+
+**[Twinning](https://github.com/carawarner/pantheon/blob/master/scripts/pantheons.py#L65)**: 20% of the time coupling produces twins; the other 80% of the time it produces a single child.
+
+**[Epithets](https://github.com/carawarner/pantheon/blob/master/scripts/gods.py#L149)**: Most gods (55%) represent 3 domains: God of X, Y, and Z. Slightly fewer gods (35%) represent two domains: God of X and Y. The remaining gods represent 1  or 4 domains.