In literary terms, a legal maxim is a very concise expression more like a term of any fundamental rule or principle. It is often pedagogical and often relates to some specific actions. The oxford dictionary of philosophy defines it as, “Generally any simple and memorable rule or guide for living; for example, ‘neither a borrower nor a lender is’.
Tennyson speaks of ‘a little hoard of maxims preaching down a daughter’s heart (Locksley Hall), and maxims have generally been associated with a ‘folksy’ or ‘copy-book’ approach to morality.”
The word maxim is taken from the Latin word ‘maxima’.
Most of the Latin Maxims originate from the medieval era in the European states where Latin was the language of preference for legal purposes.
Michael Polanyi, a Hungarian-British polymath, who made important theoretical contributions to physical chemistry, economics, and philosophy, said that maxims are important for the purpose of explicit as well as implicit modes of understanding. He said that, “Maxims are rules, the correct application of which is part of the art they govern…. Maxims can only function within a framework of personal (i.e., experiential) knowledge.”
Likewise, Sir James Mackintosh who was a Scottish jurist a Whig politician and a historian. His studies and sympathies embraced many interests. He was trained in a number of different professions such as doctor and barrister, and also worked as a journalist, judge, administrator, professor, philosopher and politician. He said that, “Maxims are the condensed Good Sense of Nations.”
Sir J.F. Stephen, an English lawyer, judge and writer, a member of the Viceregal Council and later Professor of Common Law at the Inns of Court. He wrote in his book history of criminal law in England that, “It seems to me that legal maxims, in general, are little more than pert headings of chapters. They are rather minims than maxims, for they give not a particularly great but a particularly small amount of information. As often as not, the exceptions and qualifications to them are more important than the so-called rules.”
Maxims are very prevalent for legal purposes. According to Bouvier’s Law Dictionary, 1856 a maxim is defined as “An established principle or proposition. A principle of law universally admitted, as being just and consonant with reason.”
Legal maxims are necessary as we use terms to a definition.
To avoid the use of long definitions we call it in one single word or a term. The same goes for a legal maxim. For example, take a maxim ‘Ab Initio’ which means ‘from the beginning of’ or ‘from the start of something’, so instead of writing from the beginning of the entire time in a sentence wee can use the term ab initio which is actually very helpful when it is used in the practical situation.
Each legal maxim is the concise form of a big definition and each of them came from a different source or case laws. There are many different types of legal maxims. Most of them came from the ancient Latin usage of a certain word or phrases.
The attitude of early English philosophers on the context of usage of legal maxims are of excessive praise. For example, Thomas Hobbes says in his book doctor and student that legal maxims are of the same strength as that of acts and statutes.
Not only Hobbes but also other philosophers like Francis bacon said in the preface to his book collection of maxims that maxims would be used in “deciding doubts, and helping soundness of judgment, but, further, in gracing argument, in correcting unprofitable subtlety, and reducing the same to a more sound and substantial sense of law, in reclaiming vulgar errors, and, generally, in the amendment in some measure of the very nature and complexion of the whole law.”
A similar opinion about legal maxims is found in Scotland too. There it has been observed that in the Morrisons Dictionary and other authorities and reports legal maxims are used are very frequently used. They have also been used in older scots law questions respecting the rights, remedies and liabilities of individuals are determined by the immediate usage of the legal maxims.
There are many different legal maxims that are used regularly on different judicial proceedings and other areas. Thus, we see that a legal maxim is one which elucidates a legal principle, proposition or concept. There are hundreds of legal maxims which are commonly used.
 Wikipedia, Michael Polanyi
 Wikipedia, Sir James Mackintosh
 Wikipedia, James Fitzjames Stephen