Space vs Object

A book is an object,
A book as an installation art displayed in a gallery define a space.
How does an object projects a spatial definition?
A busker define a space in an underpass,
A passer-by in an underpass is just another "object".
Thus to define space, the object must be "active", there is a force, attracting.
similar to a magnetic field.
A field is a space.
It define boundaries.
Objects on the other hand has no field, hence no boundaries and unable to be of any purpose by itself.

A sculpture or any symbolic element in an landscape does not serve any better than reading a book. It is a object scattered on the landscape.
A sculpture or statue that allows people to interact (allow people to sit on it or rollerblading on it is a form of interaction) defines a space.
The original Merlion defines a space because the scale and proportion is right. The Merlion at Sentosa is an object because the scale and proportion is wrong. It is a navigation beacon.
Maya Lin's Vietnam War Memorial is a space. It consist of primarily a wall, an object but in the correct setting becomes a powerful space.