Full Idea
I have endorsed four main theses about identity: it is unitary, it is indefinable, it is fundamental, and it is a genuine relation
Gist of Idea
Identity is unitary, indefinable, fundamental and a genuine relation
Source
Colin McGinn (Logical Properties [2000], Ch.1)
Book Reference
McGinn,Colin: 'Logical Properties' [OUP 2003], p.14
A Reaction
That it is fundamental to our thinking seems certain (but to all possible thought?). That it is a relation looks worth questioning. One might challenge unitary by comparing the identity of numbers, values, electrons and continents. I can't define it.