People who hold the first view think that Columbus's contribution to human society is enormous. First of all, he is a great navigator. When Columbus took the initiative to cross the Atlantic for the first time in human history, he didn't even have a correct and detailed navigation information about Atlantic navigation that any ocean captain has today. He relied on a Ptolemy globe, a rough and even wrong map of the world, and a controversial Atlantic chart allegedly provided by Toscanelli. In fact, Columbus sailed to the vast unknown sea area only by his own sailing experience and macro belief in the theory of the earth's sphere, which fully showed Columbus's confidence and courage. Through the investigation of Columbus's navigation technology in America, scholars believe that "his rigorous planning, careful consideration and rich experience can not help but amaze his colleagues even today." During his voyage to the Western Ocean, Columbus's discovery of geomagnetic deviation, his successful application of this discovery, his attempt to determine the longitude of the sea through astronomical positioning, and his outstanding navigation manipulation technology made great contributions to human navigation, which fully demonstrated his bold and prudent style and superb skills as an excellent navigator. The realm reached by this skill, whether it is yesterday, today or tomorrow, has the charm that will never fade.
Scholars believe that in the history of human navigation, before Columbus, whether Zheng He's large-scale voyage to the Western Ocean or Diaz's southward voyage around the Cape of Good Hope, human beings all sailed along the coast, and only Columbus was the first ocean-going navigator to cross the Atlantic Ocean. He was the first person to record the Atlantic Ocean. He carefully observed and recorded the Mazong Sea, the northeast trade winds and ocean currents, leaving a lot of information about the navigation knowledge of the Atlantic Ocean and America, which had great influence on geography, oceanography and history. He is one of those historical figures who once stood on the threshold of maritime history and took a decisive step. The significance of his successful voyage to the West is "no less than the moon landing plan and action of contemporary mankind".
In addition to affirming Columbus's achievements from the perspective of navigation, scholars believe that although someone has been to America before Columbus, "only Columbus's voyage and his' discovery' really broke the isolation of the American continent and played a role in changing world history and human destiny." Historical materialism holds that it is not human will or talent that determines history, but the supreme economic power. "Columbus's contribution is that he opened the world market, and the establishment of the world market greatly promoted the development of world history." Therefore, "it can be said that Columbus was the first person to go to the world" and "connecting the world into an organic whole is Columbus' great achievement and the starting point for evaluating him". Scholars do not deny that there are many negative motives for the "discovery" of the New World, which has brought various disasters to the American people. However, "this is a great revolution on earth and a pioneering work in human history." Columbus' discovery of the new continent will go down in history forever.
Scholars who hold a negative attitude towards Columbus believe that Columbus's greatest "achievement" should be "creating the history of early colonialism in the world". Colonists "can take brutal and cruel atrocities against all the nations in the world that they can enslave, which is unmatched by any barbaric, ignorant, cruel and shameless race at any time in the history of the world." As for Columbus himself, he was not only a gold digger and a hypocritical Christian, but also a colonial pirate. During his life, "his mental state was a little confused." Columbus colonized America and plundered gold. He initiated the slave trade, slavery and tribute system of American Indians, and was a pioneer of colonialism that enslaved the American continent. The disaster and genocide brought by Columbus to Indians are no longer ordinary class exploitation, nor the rise of workers' personal status like ordinary social changes, but heinous crimes.
Scholars who hold the third view believe that Columbus is a historical figure with dual identities. As a pioneer, he "discovered" the new continent and established the connection between the old and new continents. As a colonizer, he brutally invaded and massacred the American people. However, it was the colonial plunder that greatly promoted the transformation from feudalism to capitalism in Europe, and "15th century Indians came out of primitive barbarism and entered the era of civilization after the arrival of the first colonists in Western Europe headed by Columbus", which objectively brought new modes of production to America and "shortened the historical process of American society entering the era of capitalist civilization". "This kind of function and influence is unmatched by anyone before Columbus". Therefore, "when we assert that Columbus' activities promoted the development of capitalism, we are faced with an unavoidable problem, that is, colonialism objectively promoted the progress of history, and those pioneers of colonialism (Columbus) became advanced elements to promote history! "
Scholars who hold the fourth view believe that there are two major events in Columbus's life: one is to open up a new route across the Atlantic to America; The first is a new way of primitive accumulation through colonial plunder. This clearly shows that Columbus was a navigator in primitive accumulation of capital's time and the earliest colonist who invaded America. Dual identity, with both differences and connections, is dialectically unified in Columbus, the pioneer of capitalism. It is incomplete to see only one aspect of him. In their view, Columbus is a historical figure in the transitional era between the old and the new, and he shows the characteristics of two eras: he is a hero who discovered the new "continent" and a helper who spread colonialism; He is a devout Catholic, retaining his belief in medieval theocracy, but persistently pursuing scientific knowledge; Although his sailing career was completed under the domination of feudal mode of production, his behavior was funded by big businessmen, which objectively reflected the interests of the commercial bourgeoisie. Therefore, "in him, there is both the glory of the new era and the brand of the old era" and "he is a person who combines glory and sin", which can be described as "the culprit".