Creating your own spells? No.
Guessing the combination to unknown spells based on theories on how your current spells are put together? Possibly.
Would this require thinking? Most likely.*
* Note: Publishing combinations to spells ingame is against the PlaneShift license**. Therefor you would have to a) buy them ingame from someone who knows, and then trust they give you the right combination or b) figure them out yourself, either by randomly putting together the glyphs or by figuring out how the whole spell system works. Therefor, figuring out how spells work can be a tidious process that requires a decent amount of brain capacity, so if you\'re not in posession of this, you might just find it easier to buy the spells from others.

** Note: For those of you who might think I\'m lying, here\'s a C/P from the license: \"You may not copy, modify, publish, transmit, sell, participate in the transfer or sale or reproduce, create Derivative Works from, distribute, perform, display or in any way exploit any of the Material released under this License unless expressly permitted by the PlaneShift Team.\" So there you have it.