“The identity of indiscernibles is
an ontological principle
that states that there cannot be separate objects or entities that have
all their properties in
common. That is, entities x and y are identical if every predicate possessed
by x is also
possessed by y and
vice versa; to suppose two things indiscernible is to suppose the same thing
under two names.”
Gottfried Wilhelm Leibniz
Or, to put it simply, if two things are the same, at
least one of them doesn’t exist. Or, to put it simpler still, to exist you have to be different from everything else. A simple enough idea I picked
up in a philosophy tutorial way back and somehow have never quite shaken off.
In fact, I think of it often, and drop it into conversation. When
conversation is slow. Which can cause some problems,
because people tend not to believe you. Oh come on,
they say, what about those coffee beans. Or those baked beans. They’re all the same.
And all exist. No they’re not the same, I counter. They
have equivalent physical properties, but positionally they are quite
different, i.e. one’s here, one’s there. Therefore they’re not the same.
And the doubter retreats, not so much vanquished, as bored.