Russell needs more of the drug he has been using to get the normal high he got when he first started. russell is experiencing

Drug Tolerance

Explanation:

He is using more of the drug to compensate for his brain chemistry adapting to offset the drug effect, which requires larger doses to experience the same effects.

i believe the answer is:   psychological  experiment

in this experiment, wilhelm wundt became the first person that implement scientific method in analyzing the pyschological phenomenon.

due to this result, wilhelm wundt also able to make psychology to be acknowledged as a separate scientific field from biology.

the language of nature was a manifestation from god as he said "let there be light" and there was light the world began to assume visible, comprehensible form.

what ever we know now think of the old vision of creation we can be sure that with out the speaking of word -without language- we would have no science today with its striking power to illuminate the world.