Conventional wisdom dictates that when you run into a grizzly bear, your best bet is to remain calm and move ever so little. The same applies to most other large bears, and encounters with other potentially dangerous animals (snakes, large cats etc.) come with very similar advice: the reason being that these beasts, incapable of high level reasoning, act purely on the animal instinct that mandates the elimination of anything perceived threatening as a matter of survival. That's the basest natural element across the animal kingdom. The basest.