A favorite topic or approach. Often a compulsion. This phrase was popularized to mean this by the famous book ''The Life and Opinions of Tristram Shandy, Gentleman'' by Laurence Sterne. Every character in ''Tristram Shandy'' has a completely unhealthy obsession with one thing or another, to the exclusion of all else.

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When "Wendell" gets into a conversation, he can't help steering it toward carpentry. All his metaphors involve hammers and drills, boards and planks, pine and oak. 

When you talk to "Marsden," you inevitably wind up talking about aliens and UFOs. All technology on Earth is the result of alien intervention, so when talking about the latest Pentium, it's important that you understand our civilization borrowed that technology from the green guys. 

You can see this in many discussions. It's especially noticeable when a strong personality is involved and feels that everything reduces to [HobbyHorse]. 

Am I the only one that observes this? Anyone have any really choice examples? 

-- GarryHamilton 

Actually I run into this every time I aquire a new concept or paradigm. For some time I recognize the new pattern everywhere - until it fades into subconscious understanding. But until that point I am prone to bring the new pattern up in discussions constantly (probably to strengthen my understanding of the pattern).  -- GunnarZarncke

My HobbyHorse is that EverythingIsa HobbyHorse.

''Do you have a subscription to the FooOneOhOneInSevenDaysForDummiesInaNutshellSuperBibleUnleashed series?''

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See also: EverythingIsa, GoldenHammer