Aren&#39;t laws actually just logical axioms?
<p>For example, don't kill people. If everyone killed each other then laws wouldn't exist.
Same with theft or any other basic law.</p>
<p>Or, pay taxes. Without taxes Government would collapse and law wouldn't exist.</p>
<p>Aren't the important laws just unavoidable generic physical limitations and exist regardless of being codified?</p>

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<p>Aren't laws actually just logical axioms?</p>
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<p>No. That perspective is valid in fields such as physics and mathematics when referring to a small set of core propositions about systematically observed facts (examples are the laws of Newton, of Thermodynamics, etc.) on which a usually extensive body of knowledge is premised (examples: <em>naive</em> vs. <em>Zermelo-Fraenkel</em> set theory), but not in a context of legal systems.</p>
<p>The <a href="http://heimatundrecht.de/sites/default/files/dokumente/Black%27sLaw4th.pdf" rel="nofollow noreferrer">Black's Law Dictionary</a> defines <em>axiom</em> as &quot;<em>[a] self-evident truth; an indisputable truth</em>&quot;, whereas &quot;<em>the term [law] is [...] used in opposition to 'fact'</em>&quot; (see entry for <em>law</em>, Id). A law is &quot;<em>[t]hat which must be obeyed and followed by citizens, subject to sanctions or legal consequences</em>&quot;, <em>Id</em>. Likewise, <a href="https://en.wikipedia.org/wiki/Hans_Kelsen" rel="nofollow noreferrer">Hans Kelsen</a> defines <em>law</em> as &quot;<em>the social technique which consists in bringing about the <strong>desired</strong> social conduct of men through the threat of a measure of coercion which is to be applied in case of contrary conduct</em>&quot; (emphasis added). An axiom does not prescribe what <em>ought to be</em> (i.e., does not describe or outline the desired conduct) or how to penalize for departing from that desired conduct.</p>
<p>In the legal sense, a law is intrinsically conditional with a cause-effect structure, and people have discretion to violate it (subject to the risk of penalization). By contrast, axioms are so fundamental that they do not even have that cause-effect structure. Axioms exclusively serve as [fundamental] <em>cause</em> in the rest of propositions. The absence of cause-effect structure in axioms preempts even the possibility of <em>contrary conduct</em> (apropos of Kelsen's quote). A proposition or scenario that contravenes axioms would simply be discarded as <em>non-sequitur</em>.</p>

<h2>No</h2>
<p>Laws are not &quot;logical axioms&quot; in the technical sense. In classic (Greek) mathematics, &quot;axioms&quot; were ideas thought to be so self-evidently true that no proof of them was needed or offered. In modern (19th Century and later) mathematics, axioms are the statement that serve as the basis of a given logical/mathematical formal deductive system. They are <strong>assumed</strong> to be true, and all other statements in the system are assessed by whether they can be proved by proper deduction from the axioms or not. Note that different systems have different sets of axioms, and an axiom in one system may be a derived theorem in another, and false in a third. This technical sense of &quot;axiom&quot; can really only be applied to statements in a logical or mathematical formal deductive system.</p>
<p>In a less technical sense, an &quot;axiom&quot; may be taken to be a fundemental truth, often thought of as self-evident. For example, the opening of the <a href="https://www.archives.gov/founding-docs/declaration-transcript" rel="nofollow noreferrer">US Declaration of Independence</a>:</p>
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<p>We hold these truths to be self-evident, that all men are created equal, that they are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty and the pursuit of Happiness.--That to secure these rights, Governments are instituted among Men, deriving their just powers from the consent of the governed,</p>
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<p>was declaring those statements to be axioms in this informal sense. But note that all of them were propositions hotly debated at the time, and far from universally agreed to since.</p>
<p>The question mentions laws against killing and theft, and laws imposinmg taxes. It asks:</p>
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<p>Aren't the important laws just unavoidable generic physical limitations and exist regardless of being codified?</p>
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<p>They are not. While it is true that a society in which people frequently killed each other with no control whatsoever would not be a stable or long lasting one, many societies have existed in which killing was tolerated and even encouraged in particular circumstances. Much the same could be said of theft. And there have been stable societies with no formal governments, and others that had governments but did not have anything like modern taxation. I would venture to say that the is no law whatsoever that has existed in all known human societies in an invariable form or content. For any law, even &quot;fundamental laws&quot;, one can find a society which had very different laws on that subject.</p>
<p>As just one example, I point to saga-period Iceland, roughly during the period from 900-1260 CE. The legal system is described in some detail in Chapter 10 of  <em>Legal Systems Very Different From Ours</em> by David Friedman, <em>et al</em>. There was no king or central executive authority. There was a detailed system of laws, and a hierarchical systm of courts with four basic levels:  The local thing court or <em>Vorþing</em>; the quarter-thing for disputes between members of different things within the same quarter; the four quarter courts of the Althing (<em>alþingi</em>) or national assembly; and above the quarter courts, after the reforms credited to Njal, was the fifth court. There was a complex system of rules for what killings were acceptable. Some killings could be done freely, some required the payment of a <em>wergeld</em> or manprice, others resulted in a judgement of lesser outlawry (which was for a,limited period if the subject was able to leave Iceland) or full outlawry (which was for life).  There wer detailed laws governing marriages ans sexual relations, and many other aspects of life. There were no taxes in the modern sense, although local thingmen did pay an annual sum for the support of the local <em>goði</em> and his <em>goðorð</em> (congregation). The amount was negotiated, and a man could change to a different <em>goði</em> if the amount was too high. (The <em>goði</em> were apparently originally builders of temples to traditional deities, who served as their priests. But their fundamental importance in the legal system remained after Iceland became Christian in the year 1000, although their priestly functions ceased.)</p>
<p>Thius is just one example of a system where there was a highly developed system oi law, but many of the fundamental laws the question assumes were absent oir very different.</p>

criminal-law jurisprudence