Why is reflection called reflection instead of introspection?

language-agnostic reflection
tvanfosson picture tvanfosson · Dec 9, 2008 · Viewed 12k times · Source

What is the origin of the term reflection? It seems more like introspection. Why isn't it called that?

Introspection: A looking inward; specifically, the act or process of self-examination.

Reflection:

  1. the act of reflecting or the state of being reflected.
  2. an image; representation; counterpart
  3. a fixing of the thoughts on something; careful consideration
  4. a thought occurring in consideration or meditation.

Answer

Piotr Lesnicki picture Piotr Lesnicki · Dec 9, 2008

There is an interesting answer on the french wikipedia article for Reflection (here)

Reflection can be decomposed in two parts:

  • introspection: a program can examine itself.
  • intercession: a program can modify its state/meaning.

So reflection is a 'stronger' property than introspection. That's why you say type introspection for the ability to know types at runtime (and changing them is another action: conversion/casting).

EDIT: actually I just realized the first answer was saying exactly that ^^. Time to unplug myself...

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