If the author is reading this, <i>per se</i> means <i>by itself</i>, <i>on its own</i>. I'm not reading <i>per say</i> in its stead for the first time today.<p>It shouldn't be surprising that many misheard words survived in a time when there was no widespread frequent exchange of written language and no writing standards or before that, when hardly anyone could even read. I feel this severely complicated our languages.<p>This is slightly on topic as well, because Natural Language processing has to deal with that now.<p>going one step further with the nitpicking, just because I am at it, the per-say (or indeed, per se) is only a filler in that sentence, like <i>really</i> or <i>very</i> often are, really though.