[andrewflnr]

> For the Occam razor, adding some random term to an equation is not really better than adding some invisible but well characterized stuff...

You're being too kind. It's worse. Especially when (in my understanding anyway) that added term doesn't even explain all the things dark matter does.

[adrian_b]

Adding any finite number of parameters is strictly better than adding an infinity of parameters (i.e. an arbitrary distribution of dark matter chosen to match the observations).

[Dylan16807]

The distribution has to be consistent forward and backwards in time. It's a lot less arbitrary than you're implying, and adding a hundred parameters (or similar finite number) to gravity is not better.