Full Idea
Powers which are not essential to substance, and which include not merely an aptitude but also a certain endeavour, are exactly what are or should be meant by 'real qualities'.
Gist of Idea
The active powers which are not essential to the substance are the 'real qualities'
Source
Gottfried Leibniz (New Essays on Human Understanding [1704], 2.23)
Book Reference
Leibniz,Gottfried: 'New Essays on Human Understanding', ed/tr. Remnant/Bennett [CUP 1996], p.226
A Reaction
An important part of Leibniz's account. There are thus essential powers, in the 'depth' of the substance, and more peripheral powers, which also initiate action, and give rise to the qualities. The second must derive from the first?
Related Idea
Idea 12999 Substances are primary powers; their ways of being are the derivative powers [Leibniz]