Final answer:
The art of counterpoint in the fifteenth century was learned through an integrated system of educational institutions, largely influenced by broader cultural movements towards naturalism and realism. The increase in availability of musical compositions and theory due to the Gutenberg press complemented this learning, while music education was intensified in the churches and cathedrals of the Low Countries.
Step-by-step explanation:
In the fifteenth century, the art of counterpoint was learned through a mixture of theory and practice within a thriving cultural and educational context. The spread of polyphonic music was greatly facilitated by the invention of the Gutenberg press, which allowed for the distribution of music and musical theory on a wide scale. The Florentine renaissance was characterized by developments in painting and architecture from artists such as Filippo Brunelleschi and Masaccio, which paralleled musical developments, sharing a common drive towards realism and naturalism.
Aesthetic values changed, favoring the interval of a third, and this extended to polyphonic music, which saw a simplification early in the fourteenth century to achieve smoothness through an increased vocal range. The Low Countries' relative stability and the flourishing music education in its churches and cathedrals facilitated this education, producing skilled singers and composers in demand across Europe, especially in Italy. By the late sixteenth century, Italy had become a major center of musical activity, where practices from the North were adopted and developed into a fluid style exemplified by composers like Palestrina and Victoria.