The theme of this here essay is the notion of ‘cause’ as it is expressed by the fragments on the Presocratic philosopher Anaximander of Miletus (ca. 610 – ca. 546). I wish to argue that the idea of natural events implicitly having causes as a universal rule springs from none other then Anaximander. I also wish to argue that to Anaximander the world is governed by blind mechanism, without any final cause or cosmic supernatural principles, and finally, that to Anaximander causation (though not expressed as such) must be essential and primary in the objects of the world. In order to do so, I will begin with a discussion on the historical placement of Anaximander and the evolution of the notion of cause (part 2, The notions of aitia), where the question is stated as of where, between the aitia of ‘personal guilt’ and the aitia of ‘universal rule’, is Anaximander situated? I hope to show that he is far to the latter than often claimed. Then I will evaluate the fragments on him and discuss several interpretations of these (part 3.2; 3.3; 3.4), in order to explicate the pattern of causal explanations in Anaximander that will witness his implicit causal structure. Finally I will argue my analysis of the causation implicated by the interpretation of Anaximander (part 3.5, Causation in On nature).