Invention: "countable" or "uncountable"

[subhajit123]

I have a question related to the word "invention". Is it a countable noun or a uncountable noun? Here are some example I got on the internet.


1- invention is the talent of youth, as judgement is of age.

2- Invention is the root of innovation.

3- An invention is something that a person creates. An invention has a utility.

Why in the first to sentences the word invention is uncountable and in the third one it is countable. Can I use the word as uncountable in the third one?

 

[teechar]

Why [STRIKE]in the first to sentences[/STRIKE] is the word "invention" [STRIKE]is[/STRIKE] uncountable in the first two sentences but [STRIKE]and[/STRIKE] countable in the third? [STRIKE]one it is countable. Can I use the word as uncountable in the third one?[/STRIKE]

Here's an exercise for you: try to define what it means in the first two and what it means in the third.