US-P19.015ab सदभ्युपेतं भवतोपकल्पितं विचारहेतोर्यदि तस्य नास्तिता ।US-P19.015cd विचारहानाच् च तहैव संस्थितं न चेत् तदिष्टं नितरां सदिष्यते ॥
In plain words
Suppose that what you have imagined and allowed as existent for the sake of investigation has no existence at all. Investigation itself would fall away, and the matter would remain unsettled. If you do not accept that outcome, there is all the more reason to acknowledge what exists.
Close to the Sanskrit
Suppose that what you have imagined and conceded as existent for the sake of inquiry has no existence at all. Inquiry would then be lost, and the matter would remain as it was. If that is not accepted, existence must all the more be accepted.