"Things that are different are not the same." -- Lewis McClary?
(Texas Chess Master).
Things that are similar can often be treated very similarly or exactly the same. However, it is at times important to recall that they are only similar, or are the same in only certain characteristics, and are not exactly the same.
We sometimes discover that "A is the same as B" maybe meaning that A equals B in some respect of current significance. We must keep in mind that A and B may differ in other respects, not currently significant to us, but which may be significant at some point.
A trivial observation but one that it sometimes helps to keep in mind.
Maybe trivial, but appearently the Java designers didn't make it, or why would they have put equals() on Object?
We have a saying, "They're different, so they're different." It's the principle that explains why a system that works fine here doesn't work so well there. When circumstances are different, you have to assume that the differences won't affect the behavior of the system if you expect the behavior to be the same. Sometimes, that's a reasonable assumption, sometimes not. Sometimes it's a reasonable assumption, and still wrong. It's a saying that tempers optimism, which is often a good thing to have tempered. -- TomKreitzberg
See also SuperOverGeneralized