Specific ways in which the operation is implemented by definition is extremely diverse. First of all, we should note the distinction between explicit and implicit. First take the form of equality of two names the latter do not have this form. The former includes, in particular, the most common, genus species, also called “classical” to the second – contextual, ostensive, axiomatic, and other fundamental importance is the difference between real and nominal definitions. The first is a description of the identified objects are true or false, the second is a prescription rules which indicate how much weight should be given to newly introduced concepts, and have no truth value.

Sometimes it expresses a general principle: “do not argue about definitions” or “do not argue about words”. However, the opinion that the definitions are unwise or even pointless to argue about, is obviously, wrong. It is not consistent with the overall presentation and its tasks in everyday life and in scientific research. This view also contradicts the obvious fact that the debates about the definitions are commonplace. For this principle is, apparently, a warning that the debate about the real debate about the concepts and nominal terms, are fundamentally different. In real definition there is a description of a set of objects, and check its accuracy is to compare it with the described object. An adequate description – truly, a description that does not match reality is false. Disputes concerning the actual definitions – it is usually disputes over the validity of the descriptive statements. The nominal definition does not describe something, and something needs to implement. Therefore, the dispute here is not the truth of some description, and the appropriateness, legality, and others with their requirements. For example, somebody defines a “behemoth”” as “carnivorous mammal of the order even-toed ungulates”. In this definition one can argue that it is wrong because it is false: hippos – not predators and herbivores. But suppose someone says that he will henceforth be called “hippo” for all members of the order of reptiles, including alligators, crocodiles and these gavials. We cannot say that it is false in this case. A person who enters a new word, do not describe, but only requires – from themselves or from others – that the objects under consideration were referred to, and not another word. But the dispute is possible and appropriate here. Alligators, crocodiles, gavials and these are called “crocodile”, there is no reason to change this well-established name in the “hippo”, especially since the latter was fixed already for quite different animals. Such a replacement is impractical, it is not useful. To make matters worse, the inevitable confusion in case of renaming would bring direct harm. The objections boil down to that proposal, or even demand, to rename the hippos into crocodiles is inappropriate and ineffective. Determination of any kind can in principle be the subject of dispute. But the debate about the definitions- requirements is different than the definitions-descriptions.