Present knowledge is wholly based on past knowledge.

This reminds of a quote from Great Expectations:

“That was a memorable day to me, for it made great changes in me. But it is the same with any life. Imagine one selected day struck out of it, and think how different its course would have been. Pause you who read this, and think for a moment of the long chain of iron or gold, of thorns or flowers, that would never have bound you, but for the formation of the first link on one memorable day.”

Every action leads to another.

Every bit of knowledge leads you to obtain more.