Is this a natural discoloration of the page or are they spores?

I like to find books that stay identical or exactly the same as the first edition. That makes older books harder to find as revisions and edits take place. I've seen the PDFs that say they have the complete set but I like physical books and they have to be hardcover. Paperbacks are disgusting to me as they can easily be damaged (would love perfect binding). I've seen some sites say the total page count was around 4,100 pages or so for all 7 volumes and when I look on everyman's library, they only list 4 volumes. I want to read these books.

Edit: Page count is 4,215

A 340-year-old manual for dealing with people, and much of it is still relevant.

This is the first English edition of Baltasar Gracián’s The Courtiers Manual Oracle, or, The Art of Prudence, published in London in 1685.

Gracián was a Spanish Jesuit whose original Oráculo manual appeared in 1647: 300 short maxims about judgement, reputation, self-control, ambition and how to navigate other people without making a complete mess of things.

Some of it reads less like seventeenth-century moral philosophy than slightly ruthless modern career advice.

“Have a special care not to make ostentation of every thing, for you’ll soon come to want admirers.”

“Some new thing is to be kept in store, that we may appear with to morrow.”

And, under “Not to die the death of a Fool”:
“Some die, because they feel, and others live because they feel not.”

Even the first maxim starts with the proposition that it now takes more to make one wise man than it did seven in ancient times. Apparently everyone has always thought they were living through an unusually difficult age.

The book later acquired some formidable admirers — Schopenhauer actually translated it into German.

The binding on this copy has had a fairly hard three centuries, but somehow that seems appropriate for a book about surviving the world.

I started collecting this English translated series about 2 months ago. Excited by how many I’ve found in that time! All of these come from either book stores, thrift stores, one book fair, one major FB marketplace score, and one free little library (which I frequently donate to). The three I’ve highlighted here are recent acquisitions.

Still looking for my grail: a collection of short stories called “Eye of the Heart”, edited by Barbara Howes.

Really excited to read this after I finish The Blade Itself by Joe Abercrombie.