We are able to walk forward because

we are able to walk because of the forward and upward reaction force exerted by the earth on us.

when we walk, we push the earth backwards and downwards with our foot. We are able to do so because of the grip provided by the force of friction. The earth pushes us with an equal and opposite force as per third law of motion.Thus we are pushed by the earth in forward direction and we are able to walk.

this allows people to make the best decision or pursue the best option. when alternatives are weighed using their advantages and disadvantages, the option whose disadvantages outweigh the advantages (based on a qualitative or quantitative analysis) are shunned while those whose advantages outweigh their disadvantages are pursued.