> rather than one where the reagents need to be coerced into reacting by providing external energy being endothermic or exothermic and activation energy are o

> rather than one where the reagents need to be coerced into reacting by providing external energy being endothermic or exothermic and activation energy are orthogonal. as a matter of fact, burning wood with air is exothermic, but you don't see thees spontaneously burning until some activation energy is provided. heck, it's not even a given that all exothermic reaction are self sustaining, there's plenty that will go on producing small quantity of heat but will required external energy to sustain the reaction; sometimes it's even the same reaction but in a different environment with a different chemistry or average temperature.