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  "body": "\n## Summary\n\nA primal algebra is a finite algebra in which every finitary operation on its universe is a term operation.\nEquivalently, its basic operations form a [[functionally complete|TDZVCWYJ9F]] set.\nThe two-element Boolean algebra and the rings $\\Z_p$ for a prime $p$ are primal.\nBy [[Foster's theorem|TCD8SZW95Z]], the variety generated by a primal algebra looks just like the variety of Boolean algebras.\n\n## Explanations\n\n### L1 human\n\nIn a primal algebra, the given operations can express every function on the set.\nThe two-element Boolean algebra is the model: every truth table is a Boolean formula.\nAnother example is arithmetic modulo a prime $p$: every function on $\\set{0, 1, \\dots, p - 1}$ is a polynomial with integer coefficients, reduced modulo $p$.\nFor instance, modulo $3$ the function equal to $1$ at $0$ and $0$ elsewhere is $1 - x^2$.\n",
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