Georg Simmel and David Lockwood made important contributions to conflict theory. Simmel proposed that conflict has sociological significance as it produces or modifies communities of interest and organizations. He argued that conflict itself resolves tensions between opposing elements and aims for a type of unity, even if through the annihilation of one side. Lockwood studied conflict dimensions and types. He distinguished between typologies that classify conflicts and dimensions that can apply to all conflicts and influence their dynamics. Both theorists recognized conflict as an inherent and sometimes productive part of social relationships rather than something purely negative.