What is the most important discovery of all time?

Here are my two suggestions for the most important discovery of all time:

1. The discovery of fire. This refers to the first controlled use of fire that was said to be discovered in the Early Stone Age when one extremely smart (or extremely lucky) caveman conquered the fire and shared this gift with members of his tribe. Conquering fire provided our ancestors with light and heat, and enabled them to cook plants and animals. Fire also kept away predators and helped the procreation of our ancestors.

2. Language. The language acted as the means of transmitting gathered knowledge from one generation to other. Language is thought to have originated when early hominids first started cooperating and working together. This enabled science to constantly grow and develop by sharing 

There have been plenty of other important discoveries throughout the history of human race but these two have prominent place because they were the ones that opened the door of knowledge to humans and helped us become the most superior creatures in this planet.

We are talking here about the main building foundations of our existence because there is a good possibility that we would have gone extinct without these two vital discoveries.

No matter what science discovers in years to come, even if the science comes up with the secret of eternal life and turns us into divine creatures, fire and language will forever remain the origin of our all knowledge.