I never could have just one, or two.
The bad thing about that first drink or two is that it basically empowers your addictive voice, originating in the more primative pleasure seeking part of the brain. It gets exactly what it wants, so it gets stirred up even more.
At the same time, that first drink or two is anesthetizing your higher brain functions, where YOU actually think and reason, and can remember all the bad things that alcohol has done to you.
So those first drinks basically energize and empower the pleasure seeking monster, who doesn't give a damn about the consequences, while paralyzing your rational mind and destroying your ability to make proper decisions from that point on.
Empower the monster and immobilize the control system.
Recipe for disaster.