# 27. Rhetorical manipulation
## 27.5. Methodology/Refinements/Sub-species
### 27.5.3. Attacking Approach
#### 27.5.3.5 Circumstance Ad hominem
This is discrediting an argument only because of the advocate's interest in the claim. For example, a study of health risks of mobile phones could not be valid because the study involved research by the telephone companies.
***Parent:** [[Attacking Approaches]]*