It’s not easy being Mr. Jim Carrey

Ever since he first talked through his posterior, Jim Carrey has epitomized a modern reinvention of the kind of goofy, physical and — should we say mentally infantile — comedy that Jerry Lewis made famous. In movie after movie, Carrey (until recently) has made fools seem both funny and maybe even a bit endearing.

The original “Dumb and Dumber” (1994) is a case in point. His performance as the aggressively dim Lloyd Christmas is pure Carrey.

And this must have been intimidating for Eric Christian Olsen , who had the job of portraying the early Lloyd in the “prequel” titled, imaginatively, “Dumb and Dumberer.” If not, it should have.

Because while Olsen has the mannerisms, the facial expressions, the body language, the tone of voice, even the cracked front tooth, all correct, his performance still misfires. He just doesn’t, at heart, have Carrey’s comic abilities.

Which just goes to show once again, true genius may be easy to impersonate, but it’s truly hard to replicate.