how so

From ellipsis of "how is that so?", and also continuing Middle English how-so, hou-so, hu se (“however, in whatsoever way”). Compare West Frisian hoesa (“how so, why”), Dutch hoezo (“how so, why”), German Low German woso (“how so, why”), German wieso (“how so, why”), Swedish hurså (“how so”). By surface analysis, how + so.

• "Yet how so ere I love, I must be wife."
• "That picture wasn't much to look at, being so old and all, but Mrs. Oaks made like it looked so nice; or, that's what she said as she stared at it, looking back and forth at the picture and me like it wasn't so. Only, she just didn't know how so it wasn't. It wasn't me at all."
• "My reflection in you warbled, because you see only hints, of what I see to beacon of me. Who am I who is reflecting from you? How so do I identify my soul in you?"