Hence, Socrates is a primary substance, while man is a secondary substance.

He explained natural processes in reference to the rarefactions and condensations of this primary substance.

The key to the understanding of primary substance as something gained through methods or inquiry is called "philosophy".

Unlike materialists positivists do not make any claims about a primary substance such as matter.

For him, the primary substance was air.

Initially, therefore, it is necessary to concentrate on the primary substance or process of addiction because this may be life-threatening.

Continued abstinence from the primary substance or process of addiction.

Most people find that they have one primary substance or behaviour of addiction.

B: An article containing a primary explosive substance and not containing two or more effective protective features.

"Ferro-gusa" is a primary substance in modern ironworks industry.