Ranald Clouston

Embedding Modal Logics into Logics of Bunched Implications

We present a new proof of the embedding of the classical modal logic S4 into the logic of Boolean Bunched Implications (BBI). While the original proof is semantical, this proof is entirely syntactical. It proceeds via Hilbert-style calculi, and is built by analogy with a recently discovered proof by Godel of the embedd...