There are a number of theorems or lemmas or mathematical ideas that come to be known as eponymous tricks, a term which in this context is in no sense derogatory. Here is a list of 10 such tricks (the last of which I learned at MO):

Further Edit. And although my original interest was in eponymous (=named-after-someone) tricks, several non-eponymous tricks have been mentioned, so I'll gather those here as well:

Some of those listed above do not yet have Wikipedia pages (hint, hint—Thierry).

I (JOR) am not seeking to extend this list (although I would be incidentally interested to learn of prominent omissions), but rather I am wondering:

Is there some aspect or trait shared by the mathematical ideas or techniques that, over time, come to be named "tricks"?

I am aware this is a borderline question; feel free to close if it unduly distracts.

11 Fixing (I hope!) E-M swindle URL syntax.

There are a number of theorems or lemmas or mathematical ideas that come to be known as eponymous tricks, a term which in this context is in no sense derogatory. Here is a list of 10 such tricks (the last of which I learned at MO):

I (JOR) am not seeking to extend this list (although I would be incidentally interested to learn of prominent omissions), but rather I am wondering:

Is there some aspect or trait shared by the mathematical ideas or techniques that, over time, come to be named "tricks"?

I am aware this is a borderline question; feel free to close if it unduly distracts.

There are a number of theorems or lemmas or mathematical ideas that come to be known as eponymous tricks, a term which in this context is in no sense derogatory. Here is a list of 10 such tricks (the last of which I learned at MO):

I (JOR) am not seeking to extend this list (although I would be incidentally interested to learn of prominent omissions), but rather I am wondering:

Is there some aspect or trait shared by the mathematical ideas or techniques that, over time, come to be named "tricks"?

I am aware this is a borderline question; feel free to close if it unduly distracts.

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