ことから

ことから gives the fact that a judgment or a name rests on: "from the fact that", "judging from". It follows the plain form of a verb or an い-adjective, past or non-past, and the second half says what was concluded or how something came about.

A な-adjective takes な or である, and a noun takes である: しずか静かなことから, がくせい学生であることから. A noun with の means something else: がくせい学生のことから is "from matters concerning the student".

Where a name comes from

ことから is the standard way to explain why something is called what it is, usually with とよばれる呼ばれる or というなまえ名前がついた.

ことから or から

から gives any reason at all, including your own feelings and plans. ことから gives an observed fact as evidence, and the second half reports a judgment or a result, not a wish, an invitation or a request. ことから is formal and belongs to news, reports and explanations; in conversation, use から or ので.

• × 疲れたことから、早く寝よう → 疲れたから、早く寝よう