If our thoughts is to be clear and we are to succeed in communicating it to other people, we must have some method of fixing the meaning of the words we use. When we use a word whose meaning is not certain, we may well be asked to define it. There is a usual traditional device for doing this by indicating the class to which whatever is indicated by the term belongs and also other particular property which distinguishes it from all other members of the same class. Thus we may define a whale as a ‘marine animal that spouts’. ‘Marine animals’ in this definition indicates the general class to which the whale belongs and ‘spouts’ indicates the particular property that distinguishes whales from other such marine animals as fishes, seals, jellyfish and lobsters. In the same way, we can define an even number as a finite integer divisible by two or a democracy as a system of government in which the people themselves rule.

  there are other ways, of course of indicating the meaning of words. We may for example, find it hard to make a suitable definition of the word ‘animal’, as we say that an animal is such a thing as a rabbit, dog fish or goat. Similarly, we may say that religion is such a system as Christianity, Islam, Judaism and Buddhism. This way of indicating the meaning of a term by enumerating examples of what it includes is obviously of limited usefulness. If we indicate our use of the word ‘animal’ as above, our hearers might for example be doubtful whether a sea-anemone or a slug was to be included in the class of animals. It is however, a useful way of supplementing a definition if the definition itself id definite without being easily understandable. Failure of an attempt at definition to serve its purpose may result from giving as distinguishing mark one which either does not belong to all the things the definition id intended to include, or does belong to some members of the same general class which the definition is intended to exclude.

  Over the years there has been this hue and cry by government and the public policy advisers against the phenomenon of the rural-urban drift. Researches have been conducted on various aspects of this phenomenon which have resulted in the identification of the various causes and consequences of drift. In addition, prescriptions have been given for controlling the rural-urban drift.
Among the causes most often mentioned are population pressures in some rural areas resulting in dwindling farm lands; increase in school enrollment and the resultant rise in education levels which qualify many people for urban employment, higher wages in the urban centres relative to rural centres and the rather naïve one of the ‘bright lights’ in the cities so much touted by early foreign sociologists.
The most often mention consequences of this rural-urban migration includes depopulation of the rural area leading to overcrowding of the cities and the resultant housing and sanitation problems; decline in the agricultural population resulting in less food crops being grown and high food prices in the cities, and increasing urban unemployment. The results of the phenomenon are seen largely as negative
Measures to control the rural-urban drift includes the establishment of essential amenities like water, electricity, hospitals, colleges, and cinema houses; the location of employment generating establishment and the building of good interconnecting roads.
The sum total of these prescriptions in essence, unwittingly or paradoxically, is for the rural areas to be transformed into urban centres. This is so because to industrialize the rural areas would draw many more people out of agriculture than if industries were restricted to urban centres
When industries are located in the rural areas, it involves much less cost for the prospective rural-urban migrant to change to a non-agricultural job, than is involved in his leaving a rural abode for a distance urban centre.
Therefore, rural industrialization holds a higher potential for the de-agriculturalization of the rural population than when industries are concentrated in urban areas.
The phenomenon of rural-urban migration has been intensively and extensively researched and studied, but it would seem that it has largely been misinterpreted and misunderstood. Consequently public policies on the subject have been misdirected.