The equilibrium or balance, so to speak, between his intellectual faculties and animal propensities, seems to have been destroyed. He is fitful, irreverent, indulging at times in the grossest profanity (which was not previously his custom), manifesting but little deference for his fellows, impatient of restraint or advice when it conflicts with his desires, at times pertinaciously obstinate, yet capricious and vacillating, devising many plans of future operations, which are no sooner arranged than they are abandoned in turn for others appearing more feasible.
Sapolsky, Robert M.. Behave: The Biology of Humans at Our Best and Worst (pp. 70-71). Penguin Publishing Group. Kindle Edition.Phineas Gage, after having a 13 pound iron tamping rod blown through his skull in a blasting accident. What is DT's excuse?