Full Idea
Equals added to unequals, in time or anything else at all, always make them differ by an amount equal to that which they differed at first.
Gist of Idea
Equals added to unequals maintain the difference between them
Source
Plato (Parmenides [c.366 BCE], 154b)
A Reaction
An early assumption that entities must remain identical to themselves during any logical procedure.
Book Reference
Plato: 'Parmenides', ed/tr. Gill,M.L./Ryan,P. [Hackett 1996], p.161