What, exactly, is the difference between the following two sentences? Are they both correct -- or is one considered more correct in certain contexts or constructions?
Jim's wailing child was the subject of much scrutiny.
Jim's wailing child was the object of much scrutiny.
Each of these usages is ubiquitous, and it's not uncommon to see both within the span of a few sentences. (For example, Google estimates over 60,000 results for "subject of study" "object of study".)
The difficulty seems to be that both words have several senses, and they are somewhat overlapping in this case. As a lover of grammar, I am frustrated that I cannot resolve this question in my mind.
(I tried to search to see if this question had already been asked, but I could not find it amongst the many questions concerning pronoun declension and objects and subjects as parts of speech.)