Daniel Davis is an underappreciated talent.
I haven't much to say about the episode itself except:
@dgw As far as I understand the computer gave Moriaty the abilites in order to defeat Data. In theory that means the computer gave itself those abilities. Which raises the question: was Data trying to defeat the Enterprise computer in the form of Moriaty ? So was this a contest between two AIs ?
@finfan I tried to ignore the whole AI thing, hand-waving it away with my statement about "the huge plot hole", because it very quickly becomes a slippery slope.
The fact that Geordi's phrasing slip—"capable of defeating Data" instead of "capable of defeating Holmes"—allows the computer to create an apparently sentient AI raises some tough questions about the ship's computer itself. Not the least of which is, if the computer can create sentience, does that imply its own sentience? And from there, we start to wonder how self-destruct systems could ever be ethical in Starfleet, since the computer is essentially ordered to commit suicide.
Data went through the Academy and was sworn in as an officer. Do all shipboard computers take an oath of service, too? Even then, it doesn't eliminate the ethical considerations of ordering a ship to self-destruct. This is just a small sampling of why I consider Moriarty a plot hole.