(p.147) <i>Nineteen-Eighty Four</i>:<br/>-It<span style="color:#ff0000;">'s</span> a message from a hundred years ago, <span style="color:#ff0000;">if one knew</span> how to read it.<br/><br/>The speaker is not talking about the past with 'know'; is the past simple 'knew' used because 'if' here is the same as 'One would <span style="color:#ff0000;">wish</span>...'?