Acknowledgement Page As an artist and retired visual art professor, I'm updating my master thesis written in 1997 as a hand-crafted art book. Today I'm self-publishing a rewritten thesis as a paperback book to include more of my artwork since graduating in 1997 with my master's degree. Is it legally okay for me to use the same Acknowledgement Page in my current self-publishing book with the same title as my master's thesis, or drop it completely?
If you wrote the original Acknowledgement page, and you still feel the same way about the help you acknowledged, then I believe that it is perfectly appropriate to use the same text. You are re-expressing sentiments that you had in 1997, using your own words. It is perfectly ethical to use them.

Beyond that, though, this would be a great opportunity to update the acknowledgements. "When I first developed the work in this volume, I was indebted to the following people ... ¶ Since then I have further benefited from ..."

Your decision to publish now, was it informed by your professional experience? Has your initial vision evolved since then, thanks to a stimulating work environment? Did anyone encourage you particularly to publish the manuscript?