The straight line, a symbol of order, symmetry, organization, security, it has great importance, especially in artistic periods with a strong anthropocentric view, as in the Italian Renaissance, in which the human body was considered the highest perfection (see the studies of Leonardo and his Vitruvian Man).
Straight line in the Neoclassical period means a rejection of the earlier dramatic curves of the Baroque and it is used to obtain a formal language as simple and essential.
In the Modern Art the use of the straight line expresses essentially the same needs: the minimalist American culture, aimed at a rigorous geometric reduction, invented the skyscraper as a symbol of a pragmatic society that goes straight to the point; in the European culture the straight line has more intellectual meanings, because it is the sign of spiritualism. For example, Piet Mondrian, strict Calvinist, use straight lines in his abstract Neoplastic style creating grid systems with straight black lines, looking for a geometric balance.
The Futurism in Italy suggests a straight line "living, breathing" of "naked severity" that becomes dynamic through an internal force as vibrant as the string of an instrument.
The Annunciation by Piero della Francesca shows the use of central perspective
in the Renaissance. The construction work is based on straight lines
that converge into a single vanishing point.