No, not necessarily. Many rather complex chemical technologies were developed by sheer empiricism.
William,
That's true.
And the Camera Obscura was a very old invention.
And that's true.
The silver chloride and its reaction to light was probably discovered by many alchemists... [That is hard to know, since unlike true scientists alchemists used to keep most of what they discovered in secrecy].
And that's why we'll never really know if anyone managed it before Daguerre and his associate.
There's a famous story about a fellow who air conditioned England's Houses of Parliament in the early 1600s with a bit of mysterious machinery. Everyone marveled at the feat and many people wrote about it. However, when the royal stipend this ur-Carrier was angling for failed to be granted, he
packed everything up and went home never to show off his air conditioning technology again.
That's the sort of mindset we're facing when we start to look at developing photography much before the mid-1700s. If the inventor isn't going to get a sinecure from the Powers The Be or see the process protected legally in some manner, they're going use their discovery as a parlor trick or as a "court magician".
There's another problem at work here too; daguerreotypes have a very short shelf life. They need to be protected in airtight containers filled with an inert gas and kept out of direct light if they're to last any time at all. How many marvels produced by a "court magician" are going to be handled in that fashion? The "magic painting" of the king or sultan will only last a few years, or until the magician washes it to retrieve the silver for his next "trick".
It would be necessary a goodly amount of luck for the pieces to be thrown together, but it is perfectly possible.
According to quantum theory is perfectly possible that I'll dissolve into my component atoms then re-materialize in a vat at the Jack Daniels distillery where I'll drown in perfect contentment, but I'm not cutting down on my liquor purchases if you know what I mean.
Say, take an alchemist with practical knowledge of the camera obscura, and it is possible that he might conceive of making a sensitive surface and exposing it on the back of the camera. From there to practical photography might be just a number of empirical stumbling and lucky findings...
I'd add one important concept to that list;
printing.
I think it's no accident that Daguerre, his associate Niepce, and their English contemporary Talbot, were all involved in printing either directly or at one remove. None of the three were searching for a way to produce photographs. Daguerre was an artist who made his money by presenting huge, moving panoramic paintings at his theatre the
"Diorama", so he was wanted a way to produce large theatre sets more rapidly. Niepce and Talbot were both printers who wanted to produce lithographs more quickly for their books. You'll notice that all three were interested in reproducing and/or transferring pictures, not words or letters, but
pictures on a mass scale.
Although this is treading close to Foucalt and his mystical claptrap, I believe that printing - the mass reproduction of text - is part of the "mindset" required for photography to be envisioned.
Bill