From what I can tell, both spells accomplish basically the same thing: immobilizing an enemy for a period of time, allowing you to focus on others.

I suppose Paralyze has the advantage that you can continue whaling on a paralyzed foe, whereas a calmed one will become hostile again once attacked.

Regardless, is it redundant for a mage to have both spells? I am thinking of a Pathfinder/D&D-style cleric build, and looking through their spell list in the ol' handbooks they would have access to spells like fear and command as well as hold person. Fear & Command can be replicated by Fear and Calm spells in the Illusion tree. Hold Person would be replicated by Paralyze.

But I wonder, is it really worth it to get Paralyze when Calm can do basically the same thing?

I'm basically wondering under what circumstances you might use one spell over the other, or whether one trumps the other totally.

well, Paralyze doesn't seem to have a Leveling cap on who it works on, but does use a lot more Magicka.