Product of the Environment
A caged animal becomes a product of his environment; mankind however builds his environments to suit his needs. If someone claims that you are a product of your environment, it means the environment you live in, has become your accepted norm, and now it influences you, rather than you influencing it.
Example:
Being a product of the environment is no different than saying you are the product of your own thinking.
Being a product of the environment is no different than saying you are the product of your own thinking.