Gandon, Sébastien <br/><br/>
Relations Theory According to Augustus De Morgan 

 -  2009.<br/>							 
<br/><br/> 77 
<br/><br/> This article aims at presenting Augustus De Morgan’s interpretation of the Euclidean theory of ratios. I show that De Morgan’s reading of the Elements, Book V, fits in the frame of his own mathematical practice. I also relate De Morgan’s interpretation to his new logic of relations.