When your observations of the universe don't match up with what your theory predicts, it may just be possible that like Issac Newton, you just haven't gotten ev

When your observations of the universe don't match up with what your theory predicts, it may just be possible that like Issac Newton, you just haven't gotten everything figured out yet. There may just be more going on in the universe over the largest scales than you've figured out so far, and we're waiting for an Einstein to come along to add to what we already know. Which is not to say that our inability to detect most of the matter in the universe means that dark matter is impossible. It just seems odd to write off the other possibility given the history of science.