εἰ δὲ τύχῃ τις ἔρδων, μελίφρον' αἰτίαν ῥοαῖσι Μοισᾶν ἐνέβαλε → if someone is successful in his deeds, he casts a cause for sweet thoughts into the streams of the Muses
Use P. τὰ ὑπάρχοντα.
per se. Use P. αὐτὸς καθ' αὑτόν.