How to think quantum-logically

The quantum-logical interpretation of quantum mechanics is discussed. Logic, it is claimed, is just as empirical as geometry. Some features of the quantum-logical view of the world are listed and discussed. These are: 1) Measurement only determines what is already the case: it does not bring into existence the observable measured, or cause it to 'take on a sharp value' which it did not already possess; 2) Probability enters into quantum theory just as it enters into classical physics: through considering large ensembles; 3) The Hilbert spaces used in quantum mechanics are simply mathematical representations of various 'logical spaces'; namely, the lattices of physical propositions involved in treating the particular systems at issue in the various problems handled. The 'real meaning' of the 'state vector' of quantum mechanics is discussed. (B.R.H.)