Lord Siva symbolizes the formless and attribute less निर्गुण ब्रह्मन् – nirguna brhman. Lord Visnu symbolizes सगुण ब्रह्मन् saguna-brahma. The linga is the closest depiction of the formless. A circle is closest to the formless. The. linga symbolizes the entire cosmos. It also represents a flame. A flame always rises up and, therefore, the Siva linga is a symbol of growth and evolution.