The definition of matter I was taught is circular

[boxerfangg]

In my science class I was taught that the definition of matter was: Anything that has mass and takes up space.

I was also taught that the definition of mass was: The amount of matter something contains.

 

If we place the definition of mass into the definition of matter we get: Anything that contains matter and takes up space.

This is a circular definition. One rule of definitions is that they can't be circular.

Can anyone tell me the real definitions for these terms?

[ajb]

In my science class I was taught that the definition of matter was: Anything that has mass and takes up space.

 

Ok, so this is a reasonable starting definition of matter. However, as far as I know there is no completely agreed upon definition. Even more loosely, matter is what physical objects consist of; atoms, electrons, protons, neutrons, quarks and so on...

 

I was also taught that the definition of mass was: The amount of matter something contains.

 

Mass is a property of matter and roughly you think of this as the amount of "physical stuff".

 

Like I said, there is no completely agreed upon definition of matter and it becomes even more complicated when quantum theory comes into play.

[michel123456]

Time is missing from your definitions.

[ajb]

Time is missing from your definitions.

 

You would like to define matter as "some physical object that has mass, occupies a non-zero volume and has a non-zero duration"?

 

I think for classical mechanics and similar this would be on ok definition. So on macroscopic scales I am sure this would be ok. In everyday life this is what one would mean by matter.

 

You could the argue if a particle is matter or not, but as that is an idealised useful mathematical tool I would not worry too much about that.

[michel123456]

Something like that. Mainly because Space alone has no meaning under Relativity.

I always have the feeling that Time is very easily forgotten.

 

We know as a definition that matter occupies a certain amount of space.

We know that to travel any amount of space, matter needs time.

So we can conclude that matter needs time in order to occupy space.