A New Introduction to Modal Logic erratum

Just noticed a significant and potentially confusion causing error regarding multiply modal logics in this nonetheless excellent text. On pages 217-218 in my 1996 edition Hughes and Cresswell write:

For instance we might have a necessity operator L_{1}, say, which is stronger than L_{2} in the sense that L_{1} p \supset L_{2}p. The canonical model for such a system would obey the restriction that for all w, w' \in \text{W}, if w\text{R}_{1}w' then w\text{R}_{2}w'.

Now, that should be for all w, w' \in \text{W}, if w\text{R}_{2}w' then w\text{R}_{1}w'.

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