Aware of the volume of migrants around the world, the increase in the number of migrants in recent years, and with the aim of disseminating information about their rights and fundamental freedoms, as well as to stimulate the exchange of ideas and to formulate protection and promotion measures, the UN has proclaimed today, December 18, as "International Migrants Day".

This event gives rise to a reflection on what it means for a person, in its essence, to leave a place of origin and settle in a certain destination, often with the opposite characteristics to those of the region or nation where the person was born and then, for various reasons, says goodbye to them to start a new life elsewhere, often in very distant lands.

In theory and in the internship, in all cases of migratory movements, two basic elements are present: a ¿lack of satisfaction" with life in the present place (element of expulsion), and a ¿vague presentiment" of a better life in another place with a very different and superior future (element of attraction).

If this were not the case, if there were no powerful reasons for people to leave their place of birth, almost always with enormous sacrifices, the multiple barriers to migration (especially the psychological barrier, since migration involves a considerable collective effort staff in terms of decision, farewell, separation, mobilization, change and adaptation), would have prevented the massive spatial displacements of people that history tells us about, especially in the last two centuries, which is when the phenomenon of migration has become generalized worldwide. Among the various causes that can drive people to make the decision to emigrate, there is a basic difference between those that are specific to the zone I of origin, and those that concern the zone I of destination.

The first causes are known as push factors, as they are responsible for "expelling" emigrants from their place of birth. Traditionally, economic reasons (mismatch between the existing population in a place and the availability of jobs work) are blamed for constituting the ¿lack of satisfaction¿ as the main reason that explains most migrations.

These factors have been particularly relevant, throughout history, with respect to the young population, and especially to single and male people, who tend to move individually. However, there are many other historical and current examples, in which there are factors of subject political or religious nature, or more staff, such as social and cultural factors associated with the search for places that provide a better quality of life in global terms, and not exclusively economic.

A new push factor subject is thus configured, which is becoming more and more frequent in developed societies, as in the case of Spain and other European countries. These are societies in which individuals enjoy a high Degree of mobility social , a very modern phenomenon that is directly correlated with the mobility migration. This factor is usually more linked to married people of both sexes and of adult age, and their families, who move on group.

The great tragedy of displaced persons, stateless persons and political refugees, who are forced to leave their homes and are faced with the distressing reality of not being able to return to their homeland until the prevailing conditions change, deserves a special mention.

With regard to the causes related to the place of destination, we must speak in terms of attraction factors, which refer to the emigrant's expectations regarding the new way of life he or she intends to undertake elsewhere. Normally these expectations coincide, more or less, with the objective reality of the place of destination, but in another multitude of instances it is rather a question of that "vague presentiment" of improvement of one's own life, which in many occasions responds more to a deep longing of the spirit, than to the objective reality of the chosen destination. The latter is usually ¿much different", but not necessarily ¿much superior". This is another of the great tragedies of migration and immigrants.

The migrant person embodies the reality of the "stranger" of the Gospel, whom we must welcome and protect, just like widows and orphans: a suffering person who suffers countless hardships and humiliations in his or her desire to improve his or her life. A good purpose on our part, at the gates of Christmas, could be not to close the doors of our hearts to migrants, those brave ones.